{"transactions":[{"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":1147854,"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":"2025-05-15T21:00:29.000Z","date":"2025-05-15","kind":"grant","planned":false,"acquired":true,"shares":3586,"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 completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2026."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 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":10403,"source":{"system":"sec-edgar","filing":"0001415889-25-013220","document":"form4-05152025_050526.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588925013220/form4-05152025_050526.xml","form_type":"4"}},{"id":1514650,"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":"2024-05-16T20:15:49.000Z","date":"2024-05-15","kind":"grant","planned":false,"acquired":true,"shares":1662,"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, 2024.  Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2024, 1,662 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":6817,"source":{"system":"sec-edgar","filing":"0001415889-24-013328","document":"form4a-05162024_040535.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588924013328/form4a-05162024_040535.xml","form_type":"4/A","original_submission_date":"2024-05-15"}},{"id":1516269,"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":"2024-05-15T20:15:25.000Z","date":"2024-05-15","kind":"grant","planned":false,"acquired":true,"shares":1162,"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, 2024.  Assuming completion of the director's current term of service on the Board of Directors, these restricted stock units will vest on May 15, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2024, 1,162 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":6317,"source":{"system":"sec-edgar","filing":"0001415889-24-013220","document":"form4-05152024_040512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000141588924013220/form4-05152024_040512.xml","form_type":"4"}},{"id":1891924,"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":"2023-05-16T20:21:37.000Z","date":"2023-05-16","kind":"sale","planned":false,"acquired":false,"shares":15000,"price":129.5,"value":1942500.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held as of May 16, 2023, 1,282 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":5155,"source":{"system":"sec-edgar","filing":"0001209191-23-029797","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919123029797/doc4.xml","form_type":"4"}},{"id":1893813,"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":"2023-05-15T20:29:10.000Z","date":"2023-05-15","kind":"grant","planned":false,"acquired":true,"shares":1282,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on May 15, 2024."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this grant on of May 15, 2023, 3,971 shares 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":20155,"source":{"system":"sec-edgar","filing":"0001209191-23-029462","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919123029462/doc4.xml","form_type":"4"}},{"id":1899785,"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":"2023-05-09T20:12:22.000Z","date":"2023-05-09","kind":"sale","planned":false,"acquired":false,"shares":10000,"price":118.5,"value":1185000.0,"ownership":{"direct":true},"footnotes":[{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"Of the shares held as of May 9, 2023, 2,689 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":18873,"source":{"system":"sec-edgar","filing":"0001209191-23-028241","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919123028241/doc4.xml","form_type":"4"}},{"id":2017187,"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":"2023-02-14T21:00:53.000Z","date":"2023-02-01","kind":"sale","acquired":false,"shares":1700,"price":127.12,"value":216104.0,"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 $127.01 to $127.15, 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 February 14, 2023, 2,689 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":28873,"source":{"system":"sec-edgar","filing":"0001209191-23-009084","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919123009084/doc4.xml","form_type":"4"}},{"id":2270699,"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":"2022-05-16T20:26:01.000Z","date":"2022-05-16","kind":"grant","acquired":true,"shares":2689,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on May 16, 2023."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this grant on of May 16, 2022, 2,689 shares 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":30573,"source":{"system":"sec-edgar","filing":"0001209191-22-029136","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919122029136/doc4.xml","form_type":"4"}},{"id":2710647,"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":"2021-05-17T20:35:03.000Z","date":"2021-05-17","kind":"grant","acquired":true,"shares":3497,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on November 17, 2021."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held after this grant on of May 17, 2021, 4,907 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":27884,"source":{"system":"sec-edgar","filing":"0001209191-21-033168","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919121033168/doc4.xml","form_type":"4"}},{"id":3147559,"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":"2020-05-15T12:46:21.000Z","date":"2020-05-15","kind":"grant","acquired":true,"shares":6881,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on November 15, 2020."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2020, 11,109 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":24387,"source":{"system":"sec-edgar","filing":"0001209191-20-029471","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919120029471/doc4.xml","form_type":"4"}},{"id":3526269,"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":"2019-05-15T21:14:07.000Z","date":"2019-05-15","kind":"grant","acquired":true,"shares":6232,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on November 15, 2019."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Of the shares held as of May 15, 2019, 11,869 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":17506,"source":{"system":"sec-edgar","filing":"0001209191-19-030084","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919119030084/doc4.xml","form_type":"4"}},{"id":3928706,"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":"2018-05-17T12:10:09.000Z","date":"2018-05-16","kind":"grant","acquired":true,"shares":5637,"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.  Assuming continuation of service as a director, 25% of these restricted stock units will vest on each of May 16, 2019, May 16, 2020, May 16, 2021 and May 16, 2022."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"All of the shares held as of May 16, 2018, 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":11274,"source":{"system":"sec-edgar","filing":"0001209191-18-030755","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919118030755/doc4.xml","form_type":"4"}},{"id":3928705,"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":"2018-05-17T12:10:09.000Z","date":"2018-05-16","kind":"grant","acquired":true,"shares":5637,"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.  Assuming continuation of service on the Board of Directors, these restricted stock units will vest on November 16, 2018."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"All of the shares held as of May 16, 2018, 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":5637,"source":{"system":"sec-edgar","filing":"0001209191-18-030755","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1113232/000120919118030755/doc4.xml","form_type":"4"}}]}