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The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on September 15, 2026, 19,782 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":34816,"source":{"system":"sec-edgar","filing":"0001940017-26-000010","document":"form4-09162026_050903.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1940017/000194001726000010/form4-09162026_050903.xml","form_type":"4"}},{"id":4619762,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-09-16T21:05:08.000Z","date":"2026-09-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":136,"price":105.04,"value":14285.44,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on September 15, 2026 of service vesting restricted stock units granted to the executive in September 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on September 15, 2026, 20,590 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":27491,"source":{"system":"sec-edgar","filing":"0001990732-26-000010","document":"form4-09162026_050901.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1990732/000199073226000010/form4-09162026_050901.xml","form_type":"4"}},{"id":707235,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":29841,"kind":"person","name":"Ryzhik David","position":1,"cik":"0002123863","reported_name":"Ryzhik David","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"SVP Interim CFO"}}],"security":"Common Stock","published_at":"2026-07-17T21:05:05.000Z","date":"2026-07-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":94,"price":145.01,"value":13630.94,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on July 15, 2026 of service vesting restricted stock units granted to the executive in July 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this vesting event on July 15, 2026, 7,688 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":9790,"source":{"system":"sec-edgar","filing":"0002123863-26-000008","document":"form4-07172026_050701.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212386326000008/form4-07172026_050701.xml","form_type":"4"}},{"id":707234,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":29841,"kind":"person","name":"Ryzhik David","position":1,"cik":"0002123863","reported_name":"Ryzhik David","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"SVP Interim CFO"}}],"security":"Common Stock","published_at":"2026-07-17T21:05:05.000Z","date":"2026-07-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":127,"price":145.01,"value":18416.27,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on July 15, 2026 of service vesting restricted stock units granted to the executive in July 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"This amount includes 56 shares of common stock acquired by the reporting person on June 30, 2026 pursuant to the company's 2020 Employee Stock Purchase Plan, rounded to the nearest whole share. Of the shares held after this vesting event on July 15, 2026, 8,007 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":9884,"source":{"system":"sec-edgar","filing":"0002123863-26-000008","document":"form4-07172026_050701.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212386326000008/form4-07172026_050701.xml","form_type":"4"}},{"id":734703,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":29841,"kind":"person","name":"Ryzhik David","position":1,"cik":"0002123863","reported_name":"Ryzhik David","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"SVP Interim CFO"}}],"security":"Common Stock","published_at":"2026-06-17T21:05:06.000Z","date":"2026-06-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":76,"price":176.845,"value":13440.22,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on June 16, 2026 of service vesting restricted stock units granted to the executive in June 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on June 16, 2026, 8,439 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":9955,"source":{"system":"sec-edgar","filing":"0002123863-26-000006","document":"form4-06172026_050601.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212386326000006/form4-06172026_050601.xml","form_type":"4"}},{"id":736633,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-06-16T21:05:05.000Z","date":"2026-06-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":506,"price":191.6,"value":96949.6,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on June 15, 2026 of service vesting restricted stock units granted to the executive in June 2023. The shares issued to the executive following the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on June 15, 2026, 19,447 shares are issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":19987,"source":{"system":"sec-edgar","filing":"0001979418-26-000010","document":"form4-06162026_050601.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000010/form4-06162026_050601.xml","form_type":"4"}},{"id":749981,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":10833,"kind":"person","name":"Sayiner Necip","position":1,"cik":"0001338515","reported_name":"Sayiner Necip","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-06-04T21:05:07.000Z","date":"2026-06-03","kind":"sale","planned":false,"acquired":false,"shares":1586,"price":157.4422,"value":249703.3292,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $157.4100 to $157.7100, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on June 3, 2026, 2,110 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":7112,"source":{"system":"sec-edgar","filing":"0001338515-26-000004","document":"form4-06042026_050601.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000133851526000004/form4-06042026_050601.xml","form_type":"4"}},{"id":752568,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert 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forfeiture."}],"balance_after":17695,"source":{"system":"sec-edgar","filing":"0001339595-26-000008","document":"form4-05262026_050503.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000133959526000008/form4-05262026_050503.xml","form_type":"4"}},{"id":766518,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":44854,"kind":"person","name":"Evans Eileen","position":1,"cik":"0001715912","reported_name":"Evans Eileen","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, General Counsel and Sec'y"}}],"security":"Common 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forfeiture."}],"balance_after":20493,"source":{"system":"sec-edgar","filing":"0001979418-26-000008","document":"form4-05222026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000008/form4-05222026_050501.xml","form_type":"4"}},{"id":768494,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common 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These shares were sold in multiple transactions at prices ranging from $142.4400 to $142.6400, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this sale on May 19, 2026, 2,110 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":5473,"source":{"system":"sec-edgar","filing":"0001208109-26-000004","document":"form4-05202026_050514.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120810926000004/form4-05202026_050514.xml","form_type":"4"}},{"id":770421,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":30776,"kind":"person","name":"GRAVES GREGORY B","position":1,"cik":"0001208109","reported_name":"GRAVES GREGORY B","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-20T21:05:21.000Z","date":"2026-05-19","kind":"sale","planned":false,"acquired":false,"shares":2625,"price":141.4051,"value":371188.3875,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $141.3301 to $141.6000, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on May 19, 2026, 2,110 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":6073,"source":{"system":"sec-edgar","filing":"0001208109-26-000004","document":"form4-05202026_050514.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120810926000004/form4-05202026_050514.xml","form_type":"4"}},{"id":770419,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45764,"kind":"person","name":"KURTZWEIL JOHN T","position":1,"cik":"0001184588","reported_name":"KURTZWEIL JOHN T","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-20T21:05:19.000Z","date":"2026-05-19","kind":"sale","planned":false,"acquired":false,"shares":3500,"price":138.7917,"value":485770.95,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $138.7600 to $139.1300, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on May 19, 2026, 1,440 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":32990,"source":{"system":"sec-edgar","filing":"0001184588-26-000004","document":"form4-05202026_050512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000118458826000004/form4-05202026_050512.xml","form_type":"4"}},{"id":770418,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45763,"kind":"person","name":"Quirk Jeanne","position":1,"cik":"0001908822","reported_name":"Quirk Jeanne","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-20T21:05:17.000Z","date":"2026-05-19","kind":"sale","planned":false,"acquired":false,"shares":1789,"price":140.22,"value":250853.58,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on May 19, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":11400,"source":{"system":"sec-edgar","filing":"0001908822-26-000004","document":"form4-05202026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000190882226000004/form4-05202026_050510.xml","form_type":"4"}},{"id":770417,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:14.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":184,"price":146.24,"value":26908.16,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the reporting person in May 2022. The shares issued to the reporting person on the vesting were reduced by a number of shares having a value equal to the reporting person's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2026, 4,582 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8360,"source":{"system":"sec-edgar","filing":"0002124265-26-000008","document":"form4-05202026_050508.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000008/form4-05202026_050508.xml","form_type":"4"}},{"id":770416,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:11.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":130,"price":146.24,"value":19011.2,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the executive in May 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this vesting event on May 16, 2026, 12,578 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":15565,"source":{"system":"sec-edgar","filing":"0002101601-26-000010","document":"form4-05202026_050507.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000010/form4-05202026_050507.xml","form_type":"4"}},{"id":770415,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:11.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":182,"price":146.24,"value":26615.68,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the executive in May 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2026, 12,846 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":15695,"source":{"system":"sec-edgar","filing":"0002101601-26-000010","document":"form4-05202026_050507.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000010/form4-05202026_050507.xml","form_type":"4"}},{"id":770414,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:09.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":79,"price":146.24,"value":11552.96,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the executive in May 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this vesting event on May 16, 2026, 20,488 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35024,"source":{"system":"sec-edgar","filing":"0001940017-26-000008","document":"form4-05202026_050505.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000008/form4-05202026_050505.xml","form_type":"4"}},{"id":770413,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:09.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":111,"price":146.24,"value":16232.64,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the executive in May 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2026, 20,756 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35103,"source":{"system":"sec-edgar","filing":"0001940017-26-000008","document":"form4-05202026_050505.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000008/form4-05202026_050505.xml","form_type":"4"}},{"id":770412,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-20T21:05:07.000Z","date":"2026-05-18","kind":"tax_withholding","planned":false,"acquired":false,"shares":711,"price":146.24,"value":103976.64,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2026 of service vesting restricted stock units granted to the executive in May 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2026, 106,691 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":154900,"source":{"system":"sec-edgar","filing":"0001689237-26-000014","document":"form4-05202026_050503.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000014/form4-05202026_050503.xml","form_type":"4"}},{"id":772889,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:18.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":103,"price":155.18,"value":15983.54,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the reporting person in May 2023. The shares issued to the reporting person on the vesting were reduced by a number of shares having a value equal to the reporting person's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 5,207 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8544,"source":{"system":"sec-edgar","filing":"0002124265-26-000006","document":"form4-05192026_050513.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000006/form4-05192026_050513.xml","form_type":"4"}},{"id":772888,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:18.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":112,"price":155.18,"value":17380.16,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F6","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the reporting person in May 2024. The shares issued to the reporting person on the vesting were reduced by a number of shares having a value equal to the reporting person's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 5,557 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8647,"source":{"system":"sec-edgar","filing":"0002124265-26-000006","document":"form4-05192026_050513.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000006/form4-05192026_050513.xml","form_type":"4"}},{"id":772887,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:18.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":226,"price":155.18,"value":35070.68,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F3","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the reporting person in May 2025. The shares issued to the reporting person on the vesting were reduced by a number of shares having a value equal to the reporting person's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F5","text":"Of the shares held after this vesting event on May 15, 2026, 5,937 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8759,"source":{"system":"sec-edgar","filing":"0002124265-26-000006","document":"form4-05192026_050513.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000006/form4-05192026_050513.xml","form_type":"4"}},{"id":772886,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:18.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1168,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 6,706 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8985,"source":{"system":"sec-edgar","filing":"0002124265-26-000006","document":"form4-05192026_050513.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000006/form4-05192026_050513.xml","form_type":"4"}},{"id":772885,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":29841,"kind":"person","name":"Ryzhik David","position":1,"cik":"0002123863","reported_name":"Ryzhik David","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"SVP Interim CFO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:16.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":226,"price":155.18,"value":35070.68,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F4","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F3","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F5","text":"Of the shares held after this vesting event on May 15, 2026, 8,695 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":10031,"source":{"system":"sec-edgar","filing":"0002123863-26-000004","document":"form4-05192026_050512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212386326000004/form4-05192026_050512.xml","form_type":"4"}},{"id":772884,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":29841,"kind":"person","name":"Ryzhik David","position":1,"cik":"0002123863","reported_name":"Ryzhik David","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"SVP Interim CFO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:16.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3115,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 9,464 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":10257,"source":{"system":"sec-edgar","filing":"0002123863-26-000004","document":"form4-05192026_050512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212386326000004/form4-05192026_050512.xml","form_type":"4"}},{"id":772883,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":61,"price":155.18,"value":9465.98,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F10","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F12","text":"Of the shares held after this vesting event on May 15, 2026, 13,221 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":15877,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":6,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772882,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":170,"price":155.18,"value":26380.6,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F10","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F11","text":"Of the shares held after this vesting event on May 15, 2026, 13,346 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":15938,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772881,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":173,"price":155.18,"value":26846.14,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 13,696 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":16108,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772880,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":372,"price":155.18,"value":57726.96,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 14,052 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":16281,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772879,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1947,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 14,821 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":16653,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772878,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:14.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1947,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 12,874 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":14706,"source":{"system":"sec-edgar","filing":"0002101601-26-000008","document":"form4-05192026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000008/form4-05192026_050510.xml","form_type":"4"}},{"id":772877,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-05-19T21:05:12.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":345,"price":155.18,"value":53537.1,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 20,493 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":21654,"source":{"system":"sec-edgar","filing":"0001979418-26-000006","document":"form4-05192026_050508.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000006/form4-05192026_050508.xml","form_type":"4"}},{"id":772876,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-05-19T21:05:12.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":744,"price":155.18,"value":115453.92,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 21,206 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":21999,"source":{"system":"sec-edgar","filing":"0001979418-26-000006","document":"form4-05192026_050508.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000006/form4-05192026_050508.xml","form_type":"4"}},{"id":772875,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-05-19T21:05:12.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":2725,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 22,743 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":22743,"source":{"system":"sec-edgar","filing":"0001979418-26-000006","document":"form4-05192026_050508.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000006/form4-05192026_050508.xml","form_type":"4"}},{"id":772874,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-05-19T21:05:12.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":2725,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 20,018 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":20018,"source":{"system":"sec-edgar","filing":"0001979418-26-000006","document":"form4-05192026_050508.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000006/form4-05192026_050508.xml","form_type":"4"}},{"id":772873,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:10.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":170,"price":155.18,"value":26380.6,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F10","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F11","text":"Of the shares held after this vesting event on May 15, 2026, 20,871 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":28793,"source":{"system":"sec-edgar","filing":"0001990732-26-000006","document":"form4-05192026_050506.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000006/form4-05192026_050506.xml","form_type":"4"}},{"id":772872,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:10.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":345,"price":155.18,"value":53537.1,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 21,221 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":28963,"source":{"system":"sec-edgar","filing":"0001990732-26-000006","document":"form4-05192026_050506.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000006/form4-05192026_050506.xml","form_type":"4"}},{"id":772871,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:10.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":744,"price":155.18,"value":115453.92,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 21,934 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":29308,"source":{"system":"sec-edgar","filing":"0001990732-26-000006","document":"form4-05192026_050506.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000006/form4-05192026_050506.xml","form_type":"4"}},{"id":772870,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:10.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3504,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 23,471 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":30052,"source":{"system":"sec-edgar","filing":"0001990732-26-000006","document":"form4-05192026_050506.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000006/form4-05192026_050506.xml","form_type":"4"}},{"id":772869,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:10.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3504,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 19,967 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":26548,"source":{"system":"sec-edgar","filing":"0001990732-26-000006","document":"form4-05192026_050506.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000006/form4-05192026_050506.xml","form_type":"4"}},{"id":772865,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:08.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":177,"price":155.18,"value":27466.86,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F10","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F11","text":"Of the shares held after this vesting event on May 15, 2026, 21,131 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35214,"source":{"system":"sec-edgar","filing":"0001940017-26-000006","document":"form4-05192026_050504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000006/form4-05192026_050504.xml","form_type":"4"}},{"id":772864,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:08.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":210,"price":155.18,"value":32587.8,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 21,732 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35391,"source":{"system":"sec-edgar","filing":"0001940017-26-000006","document":"form4-05192026_050504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000006/form4-05192026_050504.xml","form_type":"4"}},{"id":772863,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:08.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":452,"price":155.18,"value":70141.36,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 22,445 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35601,"source":{"system":"sec-edgar","filing":"0001940017-26-000006","document":"form4-05192026_050504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000006/form4-05192026_050504.xml","form_type":"4"}},{"id":772862,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:08.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3115,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 23,982 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":36053,"source":{"system":"sec-edgar","filing":"0001940017-26-000006","document":"form4-05192026_050504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000006/form4-05192026_050504.xml","form_type":"4"}},{"id":772861,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:08.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3115,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 20,867 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":32938,"source":{"system":"sec-edgar","filing":"0001940017-26-000006","document":"form4-05192026_050504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000006/form4-05192026_050504.xml","form_type":"4"}},{"id":772868,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":44854,"kind":"person","name":"Evans Eileen","position":1,"cik":"0001715912","reported_name":"Evans Eileen","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, General Counsel and Sec'y"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:06.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":867,"price":155.18,"value":134541.06,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 29,823 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":32221,"source":{"system":"sec-edgar","filing":"0001715912-26-000003","document":"form4-05192026_050502.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000171591226000003/form4-05192026_050502.xml","form_type":"4"}},{"id":772867,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":44854,"kind":"person","name":"Evans Eileen","position":1,"cik":"0001715912","reported_name":"Evans Eileen","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, General Counsel and Sec'y"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:06.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3893,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 31,616 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":33088,"source":{"system":"sec-edgar","filing":"0001715912-26-000003","document":"form4-05192026_050502.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000171591226000003/form4-05192026_050502.xml","form_type":"4"}},{"id":772866,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":44854,"kind":"person","name":"Evans Eileen","position":1,"cik":"0001715912","reported_name":"Evans Eileen","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, General Counsel and Sec'y"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:06.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":3893,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 27,723 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":29195,"source":{"system":"sec-edgar","filing":"0001715912-26-000003","document":"form4-05192026_050502.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000171591226000003/form4-05192026_050502.xml","form_type":"4"}},{"id":772860,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:04.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":1453,"price":155.18,"value":225476.54,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F10","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F11","text":"Of the shares held after this vesting event on May 15, 2026, 108,161 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":155611,"source":{"system":"sec-edgar","filing":"0001689237-26-000012","document":"form4-05192026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000012/form4-05192026_050501.xml","form_type":"4"}},{"id":772859,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:04.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":1722,"price":155.18,"value":267219.96,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2026, 111,166 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":157064,"source":{"system":"sec-edgar","filing":"0001689237-26-000012","document":"form4-05192026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000012/form4-05192026_050501.xml","form_type":"4"}},{"id":772858,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:04.000Z","date":"2026-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":3716,"price":155.18,"value":576648.88,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2026 of service vesting restricted stock units granted to the executive in May 2025. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2026, 114,727 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":158786,"source":{"system":"sec-edgar","filing":"0001689237-26-000012","document":"form4-05192026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000012/form4-05192026_050501.xml","form_type":"4"}},{"id":772857,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:04.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":19466,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. In this grant, the executive may earn shares of common stock, ranging from zero to 200% of the granted units. The shares are earned based on the achievement of performance goals based on relative total shareholder return over a performance period of January 1, 2026 to December 31, 2028. Assuming continuation of employment, 100% of the earned shares will vest on measurement of performance in 2029. Unearned restricted stock units will forfeit at such time."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2026, 122,412 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":162502,"source":{"system":"sec-edgar","filing":"0001689237-26-000012","document":"form4-05192026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000012/form4-05192026_050501.xml","form_type":"4"}},{"id":772856,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-19T21:05:04.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":19466,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to one-third of the shares granted on each of May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2026, 102,946 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":143036,"source":{"system":"sec-edgar","filing":"0001689237-26-000012","document":"form4-05192026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000012/form4-05192026_050501.xml","form_type":"4"}},{"id":775573,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":13514,"kind":"person","name":"Titinger Jorge","position":1,"cik":"0001385162","reported_name":"Titinger Jorge","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:16.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":5917,"source":{"system":"sec-edgar","filing":"0001385162-26-000009","document":"form4-05182026_050512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000138516226000009/form4-05182026_050512.xml","form_type":"4"}},{"id":775572,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":13267,"kind":"person","name":"St Dennis Thomas","position":1,"cik":"0001339595","reported_name":"St Dennis Thomas","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:15.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":18595,"source":{"system":"sec-edgar","filing":"0001339595-26-000006","document":"form4-05182026_050510.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000133959526000006/form4-05182026_050510.xml","form_type":"4"}},{"id":775571,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":10833,"kind":"person","name":"Sayiner Necip","position":1,"cik":"0001338515","reported_name":"Sayiner Necip","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:14.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 2,110 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8698,"source":{"system":"sec-edgar","filing":"0001338515-26-000002","document":"form4-05182026_050509.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000133851526000002/form4-05182026_050509.xml","form_type":"4"}},{"id":775570,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45763,"kind":"person","name":"Quirk Jeanne","position":1,"cik":"0001908822","reported_name":"Quirk Jeanne","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:10.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":13189,"source":{"system":"sec-edgar","filing":"0001908822-26-000002","document":"form4-05182026_050507.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000190882226000002/form4-05182026_050507.xml","form_type":"4"}},{"id":775569,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45764,"kind":"person","name":"KURTZWEIL JOHN T","position":1,"cik":"0001184588","reported_name":"KURTZWEIL JOHN T","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:08.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":36490,"source":{"system":"sec-edgar","filing":"0001184588-26-000002","document":"form4-05182026_050505.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000118458826000002/form4-05182026_050505.xml","form_type":"4"}},{"id":775568,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":30776,"kind":"person","name":"GRAVES GREGORY B","position":1,"cik":"0001208109","reported_name":"GRAVES GREGORY B","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:07.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 2,110 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":8698,"source":{"system":"sec-edgar","filing":"0001208109-26-000002","document":"form4-05182026_050503.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120810926000002/form4-05182026_050503.xml","form_type":"4"}},{"id":775567,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":46554,"kind":"person","name":"Chiu Tzu Yin","position":1,"cik":"0001738290","reported_name":"Chiu Tzu Yin","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-18T21:05:05.000Z","date":"2026-05-15","kind":"grant","planned":false,"acquired":true,"shares":1440,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2026. Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2027."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2026, 1,440 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":11843,"source":{"system":"sec-edgar","filing":"0001738290-26-000003","document":"form4-05182026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000173829026000003/form4-05182026_050501.xml","form_type":"4"}},{"id":777534,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":43601,"kind":"person","name":"Sutton Todd","position":1,"cik":"0002124265","reported_name":"Sutton Todd","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"VP Corporate Controller"}}],"security":"Common Stock","published_at":"2026-05-15T21:05:08.000Z","date":"2026-05-14","kind":"sale","planned":false,"acquired":false,"shares":2574,"price":163.8946,"value":421864.7004,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $163.8067 to $164.1301, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on May 14, 2026, 5,538 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":7817,"source":{"system":"sec-edgar","filing":"0002124265-26-000004","document":"form4-05152026_050503.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000212426526000004/form4-05152026_050503.xml","form_type":"4"}},{"id":777533,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-05-15T21:05:05.000Z","date":"2026-05-14","kind":"sale","planned":false,"acquired":false,"shares":1015,"price":162.315,"value":164749.725,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on May 14, 2026, 17,293 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":17293,"source":{"system":"sec-edgar","filing":"0001979418-26-000004","document":"form4-05152026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000004/form4-05152026_050501.xml","form_type":"4"}},{"id":779648,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":13514,"kind":"person","name":"Titinger Jorge","position":1,"cik":"0001385162","reported_name":"Titinger Jorge","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-05-14T21:05:07.000Z","date":"2026-05-13","kind":"sale","planned":false,"acquired":false,"shares":2000,"price":164.14,"value":328280.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on May 13, 2026, 3,586 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":4477,"source":{"system":"sec-edgar","filing":"0001385162-26-000004","document":"form4-05142026_050503.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000138516226000004/form4-05142026_050503.xml","form_type":"4"}},{"id":779646,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-05-14T21:05:05.000Z","date":"2026-05-13","kind":"sale","planned":false,"acquired":false,"shares":2883,"price":160.85,"value":463730.55,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on May 13, 2026, 17,752 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":29823,"source":{"system":"sec-edgar","filing":"0001940017-26-000004","document":"form4-05142026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000004/form4-05142026_050501.xml","form_type":"4"}},{"id":781238,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-05-13T21:05:06.000Z","date":"2026-05-12","kind":"sale","planned":false,"acquired":false,"shares":2258,"price":161,"value":363538.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on May 12, 2026, 10,927 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":12759,"source":{"system":"sec-edgar","filing":"0002101601-26-000006","document":"form4-05132026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000006/form4-05132026_050501.xml","form_type":"4"}},{"id":788765,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-07T21:05:05.000Z","date":"2026-05-06","kind":"sale","planned":true,"acquired":false,"shares":7468,"price":156.75,"value":1170609.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on May 6, 2026, 83,480 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":123570,"source":{"system":"sec-edgar","filing":"0001689237-26-000010","document":"form4-05072026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000010/form4-05072026_050501.xml","form_type":"4"}},{"id":794309,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-05-04T21:05:06.000Z","date":"2026-05-01","kind":"sale","planned":true,"acquired":false,"shares":1244,"price":138.86,"value":172741.84,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on May 1, 2026, 83,480 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":131038,"source":{"system":"sec-edgar","filing":"0001689237-26-000008","document":"form4-05042026_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000008/form4-05042026_050501.xml","form_type":"4"}},{"id":803865,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-04-21T21:05:05.000Z","date":"2026-04-20","kind":"tax_withholding","planned":false,"acquired":false,"shares":907,"price":131.02,"value":118835.14,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on April 18, 2026 of service vesting restricted stock units granted to the executive in April 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on the date of the tax withholding."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting on April 18, 2026, 16,463 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":23044,"source":{"system":"sec-edgar","filing":"0001990732-26-000004","document":"form4-04212026_050401.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000004/form4-04212026_050401.xml","form_type":"4"}},{"id":820669,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-04-02T21:05:09.000Z","date":"2026-04-01","kind":"sale","planned":true,"acquired":false,"shares":1244,"price":94.06,"value":117010.64,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on April 1, 2026, 83,480 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":132282,"source":{"system":"sec-edgar","filing":"0001689237-26-000006","document":"form4-04022026_050404.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000006/form4-04022026_050404.xml","form_type":"4"}},{"id":827597,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-03-26T21:05:07.000Z","date":"2026-03-24","kind":"sale","planned":true,"acquired":false,"shares":1244,"price":90,"value":111960.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 11, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on March 24, 2026, 83,480 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture. This amount includes restricted stock units earned by the reporting person upon the achievement of 112.5% of the restricted stock units granted in 2025 based upon the achievement of 2025 performance goals."}],"balance_after":133526,"source":{"system":"sec-edgar","filing":"0001689237-26-000004","document":"form4-03262026_050303.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000004/form4-03262026_050303.xml","form_type":"4"}},{"id":869606,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-03-03T22:05:22.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":573,"price":86.58,"value":49610.34,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 10,543 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":14633,"source":{"system":"sec-edgar","filing":"0002101601-26-000004","document":"form4-03032026_050312.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000004/form4-03032026_050312.xml","form_type":"4"}},{"id":869605,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2026-03-03T22:05:20.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":1121,"price":86.58,"value":97056.18,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 16,525 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":17540,"source":{"system":"sec-edgar","filing":"0001979418-26-000002","document":"form4-03032026_050310.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941826000002/form4-03032026_050310.xml","form_type":"4"}},{"id":869604,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2026-03-03T22:05:19.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":1121,"price":86.58,"value":97056.18,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 17,570 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":23183,"source":{"system":"sec-edgar","filing":"0001990732-26-000002","document":"form4-03032026_050308.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073226000002/form4-03032026_050308.xml","form_type":"4"}},{"id":869603,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2026-03-03T22:05:17.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":723,"price":86.58,"value":62597.34,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 16,984 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":31938,"source":{"system":"sec-edgar","filing":"0001940017-26-000002","document":"form4-03032026_050305.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001726000002/form4-03032026_050305.xml","form_type":"4"}},{"id":869602,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":26937,"kind":"person","name":"COOGAN JAMES GORDON","position":1,"cik":"0001797868","reported_name":"COOGAN JAMES GORDON","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP AND CFO"}}],"security":"Common Stock","published_at":"2026-03-03T22:05:10.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":1800,"price":86.58,"value":155844.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 31,096 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":37144,"source":{"system":"sec-edgar","filing":"0001797868-26-000002","document":"form4-03032026_050303.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000179786826000002/form4-03032026_050303.xml","form_type":"4"}},{"id":869601,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2026-03-03T22:05:06.000Z","date":"2026-03-02","kind":"tax_withholding","planned":false,"acquired":false,"shares":5227,"price":86.58,"value":452553.66,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the Company's common stock on March 2, 2026, the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2026 of performance-based restricted stock units (\"2024 PRSUs\") granted to the executive in May 2024. Of the 2024 PRSUs granted, 150% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 13, 2025, with half of the earned shares vesting on February 28, 2025 and the remaining half of the earned shares vesting on February 28, 2026. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested 2024 PRSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after the vesting of the remaining 2024 PRSUs, 79,638 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":130928,"source":{"system":"sec-edgar","filing":"0001689237-26-000002","document":"form4-03032026_050301.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000168923726000002/form4-03032026_050301.xml","form_type":"4"}},{"id":888610,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":13514,"kind":"person","name":"Titinger Jorge","position":1,"cik":"0001385162","reported_name":"Titinger Jorge","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-02-23T22:05:06.000Z","date":"2026-02-20","kind":"sale","planned":false,"acquired":false,"shares":1000,"price":80,"value":80000.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on February 20, 2026, 3,586 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":6477,"source":{"system":"sec-edgar","filing":"0001385162-26-000002","document":"form4-02232026_050201.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000138516226000002/form4-02232026_050201.xml","form_type":"4"}},{"id":937625,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":41914,"kind":"person","name":"Mahoney Robert John","position":1,"cik":"0002101601","reported_name":"Mahoney Robert John","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Operations"}}],"security":"Common Stock","published_at":"2026-01-16T22:05:05.000Z","date":"2026-01-15","kind":"grant","planned":false,"acquired":true,"shares":1734,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on January 15, 2026. Assuming continuation of employment, these restricted stock units will vest as to 25% of the shares granted on each of January 15, 2027, January 15, 2028, January 15, 2029, and January 15, 2030."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this grant on January 15, 2026, 11,611 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":15206,"source":{"system":"sec-edgar","filing":"0002101601-26-000002","document":"form4-01162026_050101.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000210160126000002/form4-01162026_050101.xml","form_type":"4"}},{"id":963461,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":13514,"kind":"person","name":"Titinger Jorge","position":1,"cik":"0001385162","reported_name":"Titinger Jorge","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2025-12-18T22:05:09.000Z","date":"2025-12-17","kind":"sale","planned":false,"acquired":false,"shares":2000,"price":86.05,"value":172100.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held after this sale on December 17, 2025, 3,586 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":7477,"source":{"system":"sec-edgar","filing":"0001385162-25-000004","document":"form4-12182025_051203.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000138516225000004/form4-12182025_051203.xml","form_type":"4"}},{"id":963460,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":44854,"kind":"person","name":"Evans Eileen","position":1,"cik":"0001715912","reported_name":"Evans Eileen","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, General Counsel and Sec'y"}}],"security":"Common Stock","published_at":"2025-12-18T22:05:05.000Z","date":"2025-12-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":1378,"price":86.32,"value":118948.96,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on December 16, 2025 of 2,850 service vesting restricted stock units granted to the executive in December 2024. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on December 16, 2025, 22,934 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":24406,"source":{"system":"sec-edgar","filing":"0001715912-25-000004","document":"form4-12182025_051201.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000171591225000004/form4-12182025_051201.xml","form_type":"4"}},{"id":971694,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2025-12-12T22:05:05.000Z","date":"2025-12-11","kind":"sale","planned":false,"acquired":false,"shares":3034,"price":89.46,"value":271421.64,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $89.39 to $89.46, inclusive. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this sale on December 11, 2025, 18,661 shares were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":18661,"source":{"system":"sec-edgar","filing":"0001979418-25-000004","document":"form4-12122025_051201.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000197941825000004/form4-12122025_051201.xml","form_type":"4"}},{"id":1017128,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":26937,"kind":"person","name":"COOGAN JAMES GORDON","position":1,"cik":"0001797868","reported_name":"COOGAN JAMES GORDON","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP AND CFO"}}],"security":"Common Stock","published_at":"2025-10-17T21:05:05.000Z","date":"2025-10-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":713,"price":83.62,"value":59621.06,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on October 16, 2025 of service vesting restricted stock units granted to the executive in October 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on October 16, 2025, 34,657 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":38944,"source":{"system":"sec-edgar","filing":"0001797868-25-000004","document":"form4-10172025_051001.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000179786825000004/form4-10172025_051001.xml","form_type":"4"}},{"id":1038312,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2025-09-17T21:05:07.000Z","date":"2025-09-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":137,"price":87.3,"value":11960.1,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on September 15, 2025 of service vesting restricted stock units granted to the executive in September 2023. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on September 15, 2025, 19,706 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":24304,"source":{"system":"sec-edgar","filing":"0001990732-25-000004","document":"form4-09172025_050903.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000199073225000004/form4-09172025_050903.xml","form_type":"4"}},{"id":1038311,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2025-09-17T21:05:05.000Z","date":"2025-09-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":208,"price":87.3,"value":18158.4,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on September 15, 2025 of service vesting restricted stock units granted to the executive in September 2022. The shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on September 15, 2025, 19,120 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":32661,"source":{"system":"sec-edgar","filing":"0001940017-25-000004","document":"form4-09172025_050901.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000194001725000004/form4-09172025_050901.xml","form_type":"4"}},{"id":1108491,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":37811,"kind":"person","name":"Blumenstock Gerald M","position":1,"cik":"0001979418","reported_name":"Blumenstock Gerald M","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP, Research, Dev. & Eng."}}],"security":"Common Stock","published_at":"2025-06-17T21:05:10.000Z","date":"2025-06-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":506,"price":68.96,"value":34893.76,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on June 15, 2025 of service vesting restricted stock units granted to the executive in June 2023. The shares issued to the executive following the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on June 15, 2025, 18,661 shares are issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":21695,"source":{"system":"sec-edgar","filing":"0001415889-25-017561","document":"form4-06172025_050606.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925017561/form4-06172025_050606.xml","form_type":"4"}},{"id":1108490,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2025-06-17T21:05:07.000Z","date":"2025-06-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":734,"price":68.96,"value":50616.64,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on June 15, 2025 of service vesting restricted stock units granted to the executive in June 2021. The shares issued to the executive following the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on June 15, 2025, 19,826 are issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":32869,"source":{"system":"sec-edgar","filing":"0001415889-25-017560","document":"form4-06172025_050604.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925017560/form4-06172025_050604.xml","form_type":"4"}},{"id":1139301,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45764,"kind":"person","name":"KURTZWEIL JOHN T","position":1,"cik":"0001184588","reported_name":"KURTZWEIL JOHN T","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2025-05-21T21:05:08.000Z","date":"2025-05-20","kind":"sale","planned":false,"acquired":false,"shares":1682,"price":61.93,"value":104166.26,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $61.72 to $62.22, inclusive. The reporting person undertakes to provide to Axcelis Technologies, Inc., any security holder of Axcelis Technologies, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 20, 2025, 3,586 were issuable on vesting of restricted stock units granted to the director under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":35050,"source":{"system":"sec-edgar","filing":"0001415889-25-013958","document":"form4-05212025_050501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013958/form4-05212025_050501.xml","form_type":"4"}},{"id":1140873,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2025-05-20T20:30:15.000Z","date":"2025-05-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":190,"price":61.58,"value":11700.2,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2025 of service vesting restricted stock units granted to the executive in May 2022. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2025, 22,326 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":33603,"source":{"system":"sec-edgar","filing":"0001415889-25-013805","document":"form4-05202025_040504.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013805/form4-05202025_040504.xml","form_type":"4"}},{"id":1140872,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2025-05-20T20:30:13.000Z","date":"2025-05-17","kind":"tax_withholding","planned":false,"acquired":false,"shares":947,"price":62.01,"value":58723.47,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F4","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 17, 2025 of service-vesting restricted stock units (\"RSUs\") granted to the executive in May 2021.  As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested RSUs."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F5","text":"Of the shares held after this vest event on May 17, 2025,90,321 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":136155,"source":{"system":"sec-edgar","filing":"0001415889-25-013804","document":"form4-05202025_040501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013804/form4-05202025_040501.xml","form_type":"4"}},{"id":1140871,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45761,"kind":"person","name":"Low Russell","position":1,"cik":"0001689237","reported_name":"Low Russell","relationship":{"director":true,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"PRESIDENT AND CEO"}}],"security":"Common Stock","published_at":"2025-05-20T20:30:13.000Z","date":"2025-05-16","kind":"tax_withholding","planned":false,"acquired":false,"shares":712,"price":61.58,"value":43844.96,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F1","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 16, 2025 of service vesting restricted stock units granted to the executive in May 2022. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Of the shares held after this vesting event on May 16, 2025, 92,361 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":137142,"source":{"system":"sec-edgar","filing":"0001415889-25-013804","document":"form4-05202025_040501.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013804/form4-05202025_040501.xml","form_type":"4"}},{"id":1143479,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:33.000Z","date":"2025-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":170,"price":62.67,"value":10653.9,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 2023. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2025, 19,988 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":24441,"source":{"system":"sec-edgar","filing":"0001415889-25-013647","document":"form4-05192025_040527.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013647/form4-05192025_040527.xml","form_type":"4"}},{"id":1143478,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:33.000Z","date":"2025-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":345,"price":62.67,"value":21621.15,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 2024.  As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2025, 20,338 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":24611,"source":{"system":"sec-edgar","filing":"0001415889-25-013647","document":"form4-05192025_040527.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013647/form4-05192025_040527.xml","form_type":"4"}},{"id":1143477,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:33.000Z","date":"2025-05-15","kind":"grant","planned":false,"acquired":true,"shares":6148,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2025.  In this grant, the executive may earn shares of common stock, ranging from zero to 150% of the granted units. The shares are earned based on the achievement of 2025 performance goals. Assuming continuation of employment, 50% of the earned shares will vest on February 28, 2027, and 50% of the earned shares will vest on February 28, 2028. Unearned restricted stock units will forfeit on February 28, 2026."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"Of the shares held after this grant on May 15, 2025, 21,050 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":24956,"source":{"system":"sec-edgar","filing":"0001415889-25-013647","document":"form4-05192025_040527.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013647/form4-05192025_040527.xml","form_type":"4"}},{"id":1143476,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45357,"kind":"person","name":"Tatnall Christopher","position":1,"cik":"0001990732","reported_name":"Tatnall Christopher","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP Global Customer Operations"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:33.000Z","date":"2025-05-15","kind":"grant","planned":false,"acquired":true,"shares":6148,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2025.  Assuming continuation of employment, these restricted stock units will vest as to 25% of the shares granted on each of May 15, 2026, May 15, 2027, May 15, 2028, and May 15, 2029."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held following this grant on May 15, 2025, 14,902 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":18808,"source":{"system":"sec-edgar","filing":"0001415889-25-013647","document":"form4-05192025_040527.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013647/form4-05192025_040527.xml","form_type":"4"}},{"id":1143475,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:29.000Z","date":"2025-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":177,"price":62.67,"value":11092.59,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F8","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 2023. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F9","text":"Of the shares held after this vesting event on May 15, 2025, 22,968 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":33793,"source":{"system":"sec-edgar","filing":"0001415889-25-013646","document":"form4-05192025_040524.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013646/form4-05192025_040524.xml","form_type":"4"}},{"id":1143474,"issuer":{"id":4152,"kind":"organization","name":"AXCELIS TECHNOLOGIES INC","symbol":"ACLS"},"owners":[{"id":45762,"kind":"person","name":"Redinbo Greg","position":1,"cik":"0001940017","reported_name":"Redinbo Greg","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP MARKETING AND APPLICATIONS"}}],"security":"Common Stock","published_at":"2025-05-19T20:30:29.000Z","date":"2025-05-15","kind":"tax_withholding","planned":false,"acquired":false,"shares":209,"price":62.67,"value":13098.03,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F6","text":"Represents the closing price of the common stock on the date of the tax withholding."},{"field":"acquired","element":"transactionAcquiredDisposedCode","label":"F5","text":"This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 2024.  As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F7","text":"Of the shares held after this vesting event on May 15, 2025, 23,569 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture."}],"balance_after":33970,"source":{"system":"sec-edgar","filing":"0001415889-25-013646","document":"form4-05192025_040524.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013646/form4-05192025_040524.xml","form_type":"4"}}],"next_cursor":"2025-05-19T20:30:29.000000Z,1143474"}