{"transactions":[{"id":897367,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Common Stock","published_at":"2026-02-18T22:04:38.000Z","date":"2026-02-14","kind":"tax_withholding","planned":false,"acquired":false,"shares":3268,"price":1.89,"value":6176.52,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F3","text":"Represents shares withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting and settlement of RSUs and does not represent a sale by the Reporting Person."}],"balance_after":71916,"source":{"system":"sec-edgar","filing":"0001470831-26-000174","document":"wk-form4_1771452272.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000147083126000174/wk-form4_1771452272.xml","form_type":"4"}},{"id":897366,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Common Stock","published_at":"2026-02-18T22:04:38.000Z","date":"2026-02-14","kind":"exercise","planned":false,"acquired":true,"shares":9420,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F2","text":"Reflects the acquisition of shares of Common Stock upon vesting of previously disclosed grants of RSUs. The grants of RSUs were initially reported in Table I of the Forms 4 filed by the Reporting Person on April 10, 2024 and February 18, 2025."}],"balance_after":75184,"source":{"system":"sec-edgar","filing":"0001470831-26-000174","document":"wk-form4_1771452272.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000147083126000174/wk-form4_1771452272.xml","form_type":"4"}},{"id":897365,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Common Stock","published_at":"2026-02-18T22:04:38.000Z","date":"2026-02-13","kind":"grant","planned":false,"acquired":true,"shares":56980,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents restricted stock units (\"RSUs\"). Each RSU represents the contingent right to receive one share of the Issuer's Common Stock upon vesting and settlement. The RSUs shall vest as follows: (i) 28,490 RSUs shall vest in three equal annual installments following the grant date, with the first installment vesting on February 13, 2027, and (ii) 28,490 RSUs shall vest in full on February 13, 2029, subject to potential acceleration upon achievement of certain performance milestones."}],"balance_after":75184,"source":{"system":"sec-edgar","filing":"0001470831-26-000174","document":"wk-form4_1771452272.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000147083126000174/wk-form4_1771452272.xml","form_type":"4"}},{"id":1264275,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Common Stock","published_at":"2025-02-18T21:55:06.000Z","date":"2025-02-14","kind":"tax_withholding","planned":false,"acquired":false,"shares":1586,"price":3.18,"value":5043.48,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents shares withheld by the Issuer to satisfy tax withholding obligations in connection with the vesting and settlement of restricted stock units (\"RSUs\") and does not represent a sale by the Reporting Person."}],"balance_after":18204,"source":{"system":"sec-edgar","filing":"0001662579-25-000018","document":"wk-form4_1739915700.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000166257925000018/wk-form4_1739915700.xml","form_type":"4"}},{"id":1543920,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Stock Option (Right to Buy)","published_at":"2024-04-10T20:16:41.000Z","date":"2024-02-14","kind":"grant","planned":false,"acquired":true,"shares":27430,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"The shares underlying this option shall vest and become exercisable in sixteen equal quarterly installments following the grant date, with the first installment vesting on May 14, 2024."}],"balance_after":27430,"derivative":{"exercise_price":7.31,"expiration_date":"2034-02-13","underlying":"Common Stock","underlying_shares":27430},"source":{"system":"sec-edgar","filing":"0001662579-24-000040","document":"wk-form4_1712780190.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000166257924000040/wk-form4_1712780190.xml","form_type":"4"}},{"id":1543919,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":65931,"kind":"person","name":"Mossler Mark","position":1,"cik":"0001992219","reported_name":"Mossler Mark","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Accounting Officer"}}],"security":"Common Stock","published_at":"2024-04-10T20:16:41.000Z","date":"2024-02-14","kind":"grant","planned":false,"acquired":true,"shares":18290,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents restricted stock units (\"RSUs\"). Each RSU represents the contingent right to receive one share of the Issuer's Common Stock upon vesting and settlement. The RSUs shall vest in four equal annual installments following the grant date, with the first installment vesting on February 14, 2025."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 1,500 shares of Common Stock that were inadvertently omitted from the Form 3 filed by the Reporting Person on September 19, 2023."}],"balance_after":19790,"source":{"system":"sec-edgar","filing":"0001662579-24-000040","document":"wk-form4_1712780190.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1992219/000166257924000040/wk-form4_1712780190.xml","form_type":"4"}}]}