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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). 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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). 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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). 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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). 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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). 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OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"Pursuant to the terms of the Merger Agreement, effective as of 10 business days prior to the closing of the Merger (the \"Acceleration Date\"), each Issuer Option then outstanding and unexercised that had an exercise price per Share that was equal to or greater than the Upfront Cash Consideration (each, an \"OTM Option\"), became fully vested and exercisable up to and through the closing of regular trading on the Nasdaq Stock Market on the fifth business day following the Acceleration Date (the \"Last Exercise Date\"). OTM Options not exercised on or prior to the Last Exercise Date were cancelled and ceased to exist as of the Effective Time, and no consideration was delivered in exchange for such OTM Option."}],"balance_after":0,"derivative":{"exercise_price":125,"underlying":"Common Stock","underlying_shares":2088},"source":{"system":"sec-edgar","filing":"0001193125-26-004925","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000119312526004925/ownership.xml","form_type":"4"}},{"id":946518,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2026-01-06T23:32:59.000Z","date":"2026-01-06","kind":"disposition_to_issuer","planned":false,"acquired":false,"shares":2460,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Pursuant to the terms of the Merger Agreement, effective as of immediately prior to the Effective Time, each option to purchase shares of Common Stock (\"Issuer Option\") that was outstanding and unexercised as of immediately prior to the Effective Time and had an exercise price per Share that was less than the Upfront Cash Consideration (each, a \"Cash-Out Option\"), became fully vested and was automatically cancelled and converted into the right to receive, without interest and subject to deduction for any required tax withholding, (i) the Offer Price minus (ii) the exercise price payable per share of Common Stock underlying such Cash-Out Option."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"Pursuant to the terms of the Merger Agreement, effective as of immediately prior to the Effective Time, each option to purchase shares of Common Stock (\"Issuer Option\") that was outstanding and unexercised as of immediately prior to the Effective Time and had an exercise price per Share that was less than the Upfront Cash Consideration (each, a \"Cash-Out Option\"), became fully vested and was automatically cancelled and converted into the right to receive, without interest and subject to deduction for any required tax withholding, (i) the Offer Price minus (ii) the exercise price payable per share of Common Stock underlying such Cash-Out Option."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"Pursuant to the terms of the Merger Agreement, effective as of immediately prior to the Effective Time, each option to purchase shares of Common Stock (\"Issuer Option\") that was outstanding and unexercised as of immediately prior to the Effective Time and had an exercise price per Share that was less than the Upfront Cash Consideration (each, a \"Cash-Out Option\"), became fully vested and was automatically cancelled and converted into the right to receive, without interest and subject to deduction for any required tax withholding, (i) the Offer Price minus (ii) the exercise price payable per share of Common Stock underlying such Cash-Out Option."}],"balance_after":0,"derivative":{"exercise_price":9.0775,"underlying":"Common Stock","underlying_shares":2460},"source":{"system":"sec-edgar","filing":"0001193125-26-004925","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000119312526004925/ownership.xml","form_type":"4"}},{"id":946517,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-01-06T23:32:59.000Z","date":"2026-01-06","kind":"other","planned":false,"acquired":false,"shares":346545,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Pursuant to the terms of that certain Agreement and Plan of Merger (the \"Merger Agreement\"), by and among the Issuer, Day One Biopharmaceuticals, Inc. (\"Parent\") and Parent's direct wholly-owned subsidiary, Emerald Merger Sub, Inc. (\"Purchaser\"), dated as of November 12, 2025, the shares (the \"Shares\") of common stock, par value $0.0001 per share, of the Issuer (the \"Common Stock\") that were tendered to Purchaser prior to the expiration time of the Offer were exchanged for: (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding (the \"Upfront Cash Consideration\"), plus (ii) one non-tradeable contingent value right per Share (each, a \"CVR\"),"},{"field":"kind","element":"transactionCoding","label":"F2","text":"(continued from footnote 1) which represents the right to receive certain contingent milestone payments of up to an aggregate of $30.25 per CVR in cash, without interest and less any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent (the Upfront Cash Consideration plus one CVR, collectively, the \"Offer Price\"). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Issuer, effective as of January 6, 2026 (the \"Effective Time\"), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Pursuant to the terms of that certain Agreement and Plan of Merger (the \"Merger Agreement\"), by and among the Issuer, Day One Biopharmaceuticals, Inc. (\"Parent\") and Parent's direct wholly-owned subsidiary, Emerald Merger Sub, Inc. (\"Purchaser\"), dated as of November 12, 2025, the shares (the \"Shares\") of common stock, par value $0.0001 per share, of the Issuer (the \"Common Stock\") that were tendered to Purchaser prior to the expiration time of the Offer were exchanged for: (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding (the \"Upfront Cash Consideration\"), plus (ii) one non-tradeable contingent value right per Share (each, a \"CVR\"),"},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"(continued from footnote 1) which represents the right to receive certain contingent milestone payments of up to an aggregate of $30.25 per CVR in cash, without interest and less any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent (the Upfront Cash Consideration plus one CVR, collectively, the \"Offer Price\"). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Issuer, effective as of January 6, 2026 (the \"Effective Time\"), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F5","text":"Represents shares of Common Stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\"). Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. The Reporting Person is a Partner of BCLSI. As a result, the Reporting Person may be deemed to share voting and dispositive power with respect to the shares held by the Bain Capital Life Sciences Entities. The Reporting Person disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein."}],"balance_after":0,"source":{"system":"sec-edgar","filing":"0001193125-26-004925","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000119312526004925/ownership.xml","form_type":"4"}},{"id":946516,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2026-01-06T23:32:59.000Z","date":"2026-01-06","kind":"other","planned":false,"acquired":false,"shares":578,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Pursuant to the terms of that certain Agreement and Plan of Merger (the \"Merger Agreement\"), by and among the Issuer, Day One Biopharmaceuticals, Inc. (\"Parent\") and Parent's direct wholly-owned subsidiary, Emerald Merger Sub, Inc. (\"Purchaser\"), dated as of November 12, 2025, the shares (the \"Shares\") of common stock, par value $0.0001 per share, of the Issuer (the \"Common Stock\") that were tendered to Purchaser prior to the expiration time of the Offer were exchanged for: (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding (the \"Upfront Cash Consideration\"), plus (ii) one non-tradeable contingent value right per Share (each, a \"CVR\"),"},{"field":"kind","element":"transactionCoding","label":"F2","text":"(continued from footnote 1) which represents the right to receive certain contingent milestone payments of up to an aggregate of $30.25 per CVR in cash, without interest and less any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent (the Upfront Cash Consideration plus one CVR, collectively, the \"Offer Price\"). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Issuer, effective as of January 6, 2026 (the \"Effective Time\"), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Pursuant to the terms of that certain Agreement and Plan of Merger (the \"Merger Agreement\"), by and among the Issuer, Day One Biopharmaceuticals, Inc. (\"Parent\") and Parent's direct wholly-owned subsidiary, Emerald Merger Sub, Inc. (\"Purchaser\"), dated as of November 12, 2025, the shares (the \"Shares\") of common stock, par value $0.0001 per share, of the Issuer (the \"Common Stock\") that were tendered to Purchaser prior to the expiration time of the Offer were exchanged for: (i) $25.00 per Share, net to the stockholder in cash, without interest and less any applicable tax withholding (the \"Upfront Cash Consideration\"), plus (ii) one non-tradeable contingent value right per Share (each, a \"CVR\"),"},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"(continued from footnote 1) which represents the right to receive certain contingent milestone payments of up to an aggregate of $30.25 per CVR in cash, without interest and less any applicable tax withholding, upon the achievement of certain specified milestones in accordance with the terms and subject to the conditions of a contingent value rights agreement entered into by Parent and the rights agent (the Upfront Cash Consideration plus one CVR, collectively, the \"Offer Price\"). After completion of the tender offer, pursuant to the terms of the Merger Agreement, Purchaser merged with and into the Issuer, effective as of January 6, 2026 (the \"Effective Time\"), with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent."}],"balance_after":0,"source":{"system":"sec-edgar","filing":"0001193125-26-004925","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000119312526004925/ownership.xml","form_type":"4"}},{"id":1111482,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2025-06-13T21:10:40.000Z","date":"2025-06-12","kind":"grant","planned":false,"acquired":true,"shares":61500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"The award will vest in full on the earlier of the first anniversary of the date of grant or the date of the 2026 Annual Meeting of Stockholders of the Issuer, subject to the Reporting Person's continuous service with the Issuer on such vesting date."}],"balance_after":61500,"derivative":{"exercise_price":0.36,"expiration_date":"2035-06-11","underlying":"Common Stock","underlying_shares":61500},"source":{"system":"sec-edgar","filing":"0000950170-25-086364","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000095017025086364/ownership.xml","form_type":"4"}},{"id":1332477,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Class A Common Stock","published_at":"2024-12-13T21:30:06.000Z","date":"2024-12-11","kind":"sale","planned":false,"acquired":false,"shares":1250000,"price":88,"value":110000000.0,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of Class A Common Stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS Fund II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS Fund II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of each of BCLS Fund II and BCLS II Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Partner of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":1447267,"source":{"system":"sec-edgar","filing":"0000950170-24-136230","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000095017024136230/ownership.xml","form_type":"4"}},{"id":1479304,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-14T20:53:35.000Z","date":"2024-06-12","kind":"grant","planned":false,"acquired":true,"shares":3789,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"The shares underlying this option will vest in full on the earlier of June 12, 2025 or the date of the Issuer's next annual meeting of stockholders, subject to continued service to the Issuer through such vesting date."}],"balance_after":3789,"derivative":{"exercise_price":80.03,"expiration_date":"2034-06-12","underlying":"Class A Common Stock","underlying_shares":3789},"source":{"system":"sec-edgar","filing":"0000950170-24-073762","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000095017024073762/ownership.xml","form_type":"4"}},{"id":1479303,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Class A Common Stock","published_at":"2024-06-14T20:53:35.000Z","date":"2024-06-12","kind":"grant","planned":false,"acquired":true,"shares":2499,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"The shares reported in this transaction represent Restricted Stock Units (\"RSUs\"). Each RSU represents the contingent right to receive one share of the Issuer's Class A Common Stock. 100% of the RSUs subject to this grant will vest on the earlier of June 12, 2025 or the date of the Issuer's next annual meeting of stockholders, subject to continued service to the Issuer through such vesting date."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The shares reported in this transaction represent Restricted Stock Units (\"RSUs\"). Each RSU represents the contingent right to receive one share of the Issuer's Class A Common Stock. 100% of the RSUs subject to this grant will vest on the earlier of June 12, 2025 or the date of the Issuer's next annual meeting of stockholders, subject to continued service to the Issuer through such vesting date."}],"balance_after":2499,"source":{"system":"sec-edgar","filing":"0000950170-24-073762","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000095017024073762/ownership.xml","form_type":"4"}},{"id":1481975,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2024-06-12T21:31:06.000Z","date":"2024-06-11","kind":"grant","planned":false,"acquired":true,"shares":55000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"The award will vest in full on the earlier of the first anniversary of the date of grant or the date of the 2025 Annual Meeting of Stockholders of the Issuer, subject to the Reporting Person's continuous service with the Issuer on such vesting date."}],"balance_after":55000,"derivative":{"exercise_price":2.26,"expiration_date":"2034-06-10","underlying":"Common Stock","underlying_shares":55000},"source":{"system":"sec-edgar","filing":"0000950170-24-072570","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000095017024072570/ownership.xml","form_type":"4"}},{"id":1557638,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Class A Common Stock","published_at":"2024-03-29T21:15:09.000Z","date":"2024-03-27","kind":"sale","planned":false,"acquired":false,"shares":791795,"price":72.31,"value":57254696.45,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of Class A Common Stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS Fund II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS Fund II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of each of BCLS Fund II and BCLS II Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Partner of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":2697267,"source":{"system":"sec-edgar","filing":"0000950170-24-038756","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000095017024038756/ownership.xml","form_type":"4"}},{"id":1557637,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Class A Common Stock","published_at":"2024-03-29T21:15:09.000Z","date":"2024-03-27","kind":"sale","planned":false,"acquired":false,"shares":88205,"price":76.8807,"value":6781262.1435,"ownership":{"direct":false,"nature":"See footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $76.46 to $77.44, inclusive. The reporting person undertakes to provide to Nuvalent, Inc., any security holder of Nuvalent, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of Class A Common Stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS Fund II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS Fund II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of each of BCLS Fund II and BCLS II Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Partner of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3489062,"source":{"system":"sec-edgar","filing":"0000950170-24-038756","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000095017024038756/ownership.xml","form_type":"4"}},{"id":1811120,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":915000,"source":{"system":"sec-edgar","filing":"0000950170-23-041402","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000095017023041402/ownership.xml","form_type":"4"}},{"id":1852601,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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Dr. Hack is a Partner of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":2415000,"source":{"system":"sec-edgar","filing":"0000899243-23-015776","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924323015776/doc4.xml","form_type":"4"}},{"id":1858677,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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The release of RSU shares shall be mandatorily deferred six months and one day after the Reporting Person no longer provides services to the Company."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"The Reporting Person has reported prior awards of RSUs in Table II of Form 4. The total reported in Column 5 includes 5,357 newly awarded RSUs and 5,357 RSUs previously reported in Table II."}],"balance_after":10714,"source":{"system":"sec-edgar","filing":"0000899243-23-014173","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924323014173/doc4.xml","form_type":"4"}},{"id":1885442,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (3) and (4) to this Form 4."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. 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The release of RSU shares shall be mandatorily deferred until the Reporting Person no longer provides services to the Company."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Each Restricted Stock Unit (\"RSU\") represents a contingent right to receive one share of common stock. The RSU will fully vest one year from the date of grant, provided that Reporting Person continues to provide services to the Company through such vesting date. The release of RSU shares shall be mandatorily deferred until the Reporting Person no longer provides services to the Company."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F1","text":"Each Restricted Stock Unit (\"RSU\") represents a contingent right to receive one share of common stock. The RSU will fully vest one year from the date of grant, provided that Reporting Person continues to provide services to the Company through such vesting date. The release of RSU shares shall be mandatorily deferred until the Reporting Person no longer provides services to the Company."}],"balance_after":5357,"derivative":{"underlying":"Common Stock","underlying_shares":5357},"source":{"system":"sec-edgar","filing":"0000899243-22-019955","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924322019955/doc4.xml","form_type":"4"}},{"id":2255136,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8568154,"source":{"system":"sec-edgar","filing":"0000899243-22-019801","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322019801/doc4.xml","form_type":"4"}},{"id":2255135,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (3) through (5) to this Form 4."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8302999,"source":{"system":"sec-edgar","filing":"0000899243-22-019274","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322019274/doc4.xml","form_type":"4"}},{"id":2259923,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8287400,"source":{"system":"sec-edgar","filing":"0000899243-22-019274","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322019274/doc4.xml","form_type":"4"}},{"id":2259922,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (3) through (5) to this Form 4."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (3) through (5) to this Form 4."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. 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Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":7120116,"source":{"system":"sec-edgar","filing":"0000899243-22-014730","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322014730/doc4.xml","form_type":"4"}},{"id":2408414,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":6522030,"source":{"system":"sec-edgar","filing":"0000899243-22-005224","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322005224/doc4.xml","form_type":"4"}},{"id":2443724,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":5385667,"source":{"system":"sec-edgar","filing":"0000899243-22-000588","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322000588/doc4.xml","form_type":"4"}},{"id":2454158,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCIP Life Sciences Associates, LP (\"BCIPLS\") and BCLS II Investco, LP (\"BCLS II Investco\" and, together with BCLS II and BCIPLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":4570667,"source":{"system":"sec-edgar","filing":"0000899243-22-000158","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924322000158/doc4.xml","form_type":"4"}},{"id":2588737,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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On August 27, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 1,891 shares of Series B Convertible Preferred Stock into an aggregate of 1,891,000 shares of the Issuer's common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"Each share of Series B Convertible Preferred Stock was convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and had no expiration date. The Series B Convertible Preferred Stock was not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 27, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 1,891 shares of Series B Convertible Preferred Stock into an aggregate of 1,891,000 shares of the Issuer's common stock."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F3","text":"Each share of Series B Convertible Preferred Stock was convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and had no expiration date. The Series B Convertible Preferred Stock was not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 27, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 1,891 shares of Series B Convertible Preferred Stock into an aggregate of 1,891,000 shares of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held directly by Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":0,"derivative":{"exercise_price":0,"exercise_date":"2019-08-12","underlying":"Common Stock","underlying_shares":1891000},"source":{"system":"sec-edgar","filing":"0000899243-21-034455","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321034455/doc4.xml","form_type":"4"}},{"id":2588736,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8415000,"source":{"system":"sec-edgar","filing":"0000899243-21-034455","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321034455/doc4.xml","form_type":"4"}},{"id":2588735,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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On August 27, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 1,891 shares of Series B Convertible Preferred Stock into an aggregate of 1,891,000 shares of the Issuer's common stock."},{"field":"shares","element":"transactionShares","label":"F3","text":"Each share of Series B Convertible Preferred Stock was convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and had no expiration date. The Series B Convertible Preferred Stock was not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 27, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 1,891 shares of Series B Convertible Preferred Stock into an aggregate of 1,891,000 shares of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held directly by Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":10415000,"source":{"system":"sec-edgar","filing":"0000899243-21-034455","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321034455/doc4.xml","form_type":"4"}},{"id":2607401,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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On August 9, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 2,249 shares of Series B Convertible Preferred Stock into an aggregate of 2,249,000 shares of the Issuer's common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"Each share of Series B Convertible Preferred Stock is convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and has no expiration date. The Series B Convertible Preferred Stock is not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 9, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 2,249 shares of Series B Convertible Preferred Stock into an aggregate of 2,249,000 shares of the Issuer's common stock."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F3","text":"Each share of Series B Convertible Preferred Stock is convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and has no expiration date. The Series B Convertible Preferred Stock is not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 9, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 2,249 shares of Series B Convertible Preferred Stock into an aggregate of 2,249,000 shares of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held directly by Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":1891,"derivative":{"exercise_price":0,"exercise_date":"2019-08-12","underlying":"Common Stock","underlying_shares":2249000},"source":{"system":"sec-edgar","filing":"0000899243-21-032571","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321032571/doc4.xml","form_type":"4"}},{"id":2607400,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8524000,"source":{"system":"sec-edgar","filing":"0000899243-21-032571","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321032571/doc4.xml","form_type":"4"}},{"id":2607399,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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On August 9, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 2,249 shares of Series B Convertible Preferred Stock into an aggregate of 2,249,000 shares of the Issuer's common stock."},{"field":"shares","element":"transactionShares","label":"F3","text":"Each share of Series B Convertible Preferred Stock is convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock and has no expiration date. The Series B Convertible Preferred Stock is not convertible if, as a result of such conversion, the holder, together with its affiliates, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then issued and outstanding immediately after giving effect to the conversion. On August 9, 2021, the Bain Capital Life Sciences Entities converted an aggregate of 2,249 shares of Series B Convertible Preferred Stock into an aggregate of 2,249,000 shares of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held directly by Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":10774000,"source":{"system":"sec-edgar","filing":"0000899243-21-032571","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321032571/doc4.xml","form_type":"4"}},{"id":2615312,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":0,"derivative":{"underlying":"Class A Common Stock","underlying_shares":2693014},"source":{"system":"sec-edgar","filing":"0000899243-21-031627","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000089924321031627/doc4.xml","form_type":"4"}},{"id":2615311,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3428014,"source":{"system":"sec-edgar","filing":"0000899243-21-031627","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000089924321031627/doc4.xml","form_type":"4"}},{"id":2615310,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. As a result, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":2693014,"source":{"system":"sec-edgar","filing":"0000899243-21-031627","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1861560/000089924321031627/doc4.xml","form_type":"4"}},{"id":2621421,"issuer":{"id":29892,"kind":"organization","name":"Nuvalent, Inc.","symbol":"NUVL"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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(\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":0,"derivative":{"exercise_price":4.5,"exercise_date":"2019-08-12","expiration_date":"2022-02-12","underlying":"Common Stock","underlying_shares":2916250},"source":{"system":"sec-edgar","filing":"0000899243-21-023297","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924321023297/doc4.xml","form_type":"4"}},{"id":2687289,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II, the \"Bain Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of the BCLS II, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3695667,"source":{"system":"sec-edgar","filing":"0000899243-21-001552","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924321001552/doc4.xml","form_type":"4"}},{"id":2909561,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II, the \"Bain Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of the BCLS II, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3620667,"source":{"system":"sec-edgar","filing":"0000899243-21-001552","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924321001552/doc4.xml","form_type":"4"}},{"id":2909560,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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The reporting person undertakes to provide to Mersana Therapeutics, Inc., any security holder of Mersana Therapeutics, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II, the \"Bain Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of the BCLS II, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3545667,"source":{"system":"sec-edgar","filing":"0000899243-21-001552","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924321001552/doc4.xml","form_type":"4"}},{"id":2975197,"issuer":{"id":130904,"kind":"organization","name":"Allena Pharmaceuticals, Inc.","symbol":"ALNA"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares held directly by Bain Capital Life Sciences Fund II, L.P. 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Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":1982469},"source":{"system":"sec-edgar","filing":"0000899243-20-030340","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1593899/000089924320030340/doc4.xml","form_type":"4"}},{"id":2994202,"issuer":{"id":5580,"kind":"organization","name":"Atea Pharmaceuticals, Inc."},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco, and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":0,"derivative":{"underlying":"Common Stock","underlying_shares":3383190},"source":{"system":"sec-edgar","filing":"0000899243-20-030340","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1593899/000089924320030340/doc4.xml","form_type":"4"}},{"id":2994201,"issuer":{"id":5580,"kind":"organization","name":"Atea Pharmaceuticals, Inc."},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2020-11-04T02:36:19.000Z","date":"2020-11-03","kind":"purchase","acquired":true,"shares":250000,"price":24,"value":6000000.0,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"shares","element":"transactionShares","label":"F4","text":"On November 3, 2020, BCLS II Investco purchased 250,000 shares of common stock of the Issuer at a price of $24.00 per share, pursuant to an underwritten public offering."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco, and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":5615659,"source":{"system":"sec-edgar","filing":"0000899243-20-030340","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1593899/000089924320030340/doc4.xml","form_type":"4"}},{"id":2994200,"issuer":{"id":5580,"kind":"organization","name":"Atea Pharmaceuticals, Inc."},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2020-11-04T02:36:19.000Z","date":"2020-11-03","kind":"exercise","acquired":true,"shares":5365659,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The preferred stock was convertible at any time, at the holder's election and had no expiration date. Each share of preferred stock was automatically converted into one share of common stock upon the closing of the Issuer's initial public offering of its common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\"), BCLS II Investco, LP (\"BCLS II Investco\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II and BCLS II Investco, the \"Bain Capital Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") (i) is the ultimate general partner of each of BCLS II and BCLS II Investco, and (ii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Dr. Hack is a Managing Director of BCLSI. By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":5365659,"source":{"system":"sec-edgar","filing":"0000899243-20-030340","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1593899/000089924320030340/doc4.xml","form_type":"4"}},{"id":2997175,"issuer":{"id":5580,"kind":"organization","name":"Atea Pharmaceuticals, Inc."},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2020-10-30T21:18:05.000Z","date":"2020-10-29","kind":"grant","acquired":true,"shares":80000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"The option vests and becomes exercisable in 36 equal monthly installments following October 29, 2020."}],"balance_after":80000,"derivative":{"exercise_price":24,"expiration_date":"2030-10-28","underlying":"Common Stock","underlying_shares":80000},"source":{"system":"sec-edgar","filing":"0000899243-20-029945","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1593899/000089924320029945/doc4.xml","form_type":"4"}},{"id":3000203,"issuer":{"id":145747,"kind":"organization","name":"BCLS Acquisition Corp.","symbol":"BLSA"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":true,"ten_percent_owner":true,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Class A ordinary shares","published_at":"2020-10-26T16:30:15.000Z","date":"2020-10-26","kind":"grant","acquired":true,"shares":487500,"price":10,"value":4875000.0,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The reported Class A ordinary shares were purchased from the Issuer in a private placement by BCLS Acquisition Holdings, LP (the \"Sponsor\") for $10.00 per share, as described in the Issuer's registration statement on Form S-1 (File No. 333-249284)."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"The shares are held by the Sponsor. The Sponsor is controlled by its general partner, BCLS Acquisition Holdings (GP), LLC (the \"General Partner\"), which is governed by a board of managers consisting of three managers. Each manager has one vote, and the approval of a majority of the managers is required to approve an action on behalf of the Sponsor. Andrew Hack serves on the board of managers of the General Partner. As a result, Dr. Hack may be deemed to share beneficial ownership of the shares held by the Sponsor. Dr. Hack disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein."}],"balance_after":487500,"source":{"system":"sec-edgar","filing":"0000899243-20-029242","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1823200/000089924320029242/doc4.xml","form_type":"4"}},{"id":3097499,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (right to buy)","published_at":"2020-06-30T00:36:09.000Z","date":"2020-06-25","kind":"grant","acquired":true,"shares":9200,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"The option vests in full on the earlier of the first anniversary of the date of grant or the date of the 2021 Annual Meeting of Stockholders of Mersana Therapeutics, Inc."}],"balance_after":9200,"derivative":{"exercise_price":22.9,"expiration_date":"2030-06-25","underlying":"Common Stock","underlying_shares":9200},"source":{"system":"sec-edgar","filing":"0001209191-20-039303","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000120919120039303/doc4.xml","form_type":"4"}},{"id":3131048,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option (Right to Buy)","published_at":"2020-05-29T16:30:53.000Z","date":"2020-05-28","kind":"grant","acquired":true,"shares":18750,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Not applicable."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option vests fully on May 28, 2021, on the one year anniversary of the grant."}],"balance_after":18750,"derivative":{"exercise_price":4.84,"expiration_date":"2027-05-27","underlying":"Common Stock","underlying_shares":18750},"source":{"system":"sec-edgar","filing":"0000899243-20-014556","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924320014556/doc4.xml","form_type":"4"}},{"id":3132587,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2020-05-28T17:13:10.000Z","date":"2020-05-27","kind":"purchase","acquired":true,"shares":1000000,"price":5,"value":5000000.0,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"On May 27, 2020, Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, collectively with BCLS, the \"Bain Life Sciences Entities\") purchased, in the aggregate, 1,000,000 shares of common stock of the Issuer at a price of $5.00 per share, pursuant to an underwritten public offering."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Represents shares of common stock held directly by the Bain Life Sciences Entities."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS.  Dr. Hack is a Managing Director of BCLSI.  By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities.  Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":8525000,"source":{"system":"sec-edgar","filing":"0000899243-20-014431","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924320014431/doc4.xml","form_type":"4"}},{"id":3178964,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2020-04-09T20:11:12.000Z","date":"2020-04-07","kind":"purchase","acquired":true,"shares":645667,"price":7.74,"value":4997462.58,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II, the \"Bain Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of the BCLS II, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS.  Dr. Hack is a Managing Director of BCLSI.  By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities.  Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":3445667,"source":{"system":"sec-edgar","filing":"0000899243-20-010592","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924320010592/doc4.xml","form_type":"4"}},{"id":3178963,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2020-04-09T20:11:12.000Z","date":"2020-04-07","kind":"purchase","acquired":true,"shares":2800000,"price":5.59,"value":15652000.0,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents shares of common stock held directly by Bain Capital Life Sciences Fund II, L.P. (\"BCLS II\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS II, the \"Bain Life Sciences Entities\")."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of the BCLS II, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS.  Dr. Hack is a Managing Director of BCLSI.  By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities.  Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":2800000,"source":{"system":"sec-edgar","filing":"0000899243-20-010592","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1442836/000089924320010592/doc4.xml","form_type":"4"}},{"id":3213983,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Right to Exchange","published_at":"2020-03-12T16:23:20.000Z","date":"2020-03-11","kind":"grant","acquired":true,"shares":1,"price":0,"value":0.0,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"On March 11, 2020, each of Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Life Sciences Entities\") entered into a letter agreement with the Issuer that provides the Bain Life Sciences Entities with the right, on one occasion, to exchange all or any portion of the warrants to purchase an aggregate of 2,916,250 shares of the Issuer's common stock (each, a \"Warrant\") owned by the Bain Life Sciences Entities for one or more warrants (each, a \"Preferred Warrant\") to purchase shares of the Issuer's non-voting Series C Convertible Preferred Stock (the \"Series C Preferred Stock\").  Each share of Series C Preferred Stock will be convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock."},{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F2","text":"(Continued from footnote 1) Each Preferred Warrant issued in exchange for a Warrant will have an exercise price of $4,500 per share of Series C Preferred Stock and will be exercisable for a number of shares of Series C Preferred Stock equal to (x) the number of shares of Common Stock for which the Warrant then remains exercisable, divided by (y) 1,000.  The Warrants, the Series C Preferred Stock and the Series B Convertible Preferred Stock held by the Bain Life Sciences Entities each include provisions prohibiting exercise or conversion into the Issuer's common stock to the extent such exercise or conversion would result in beneficial ownership of the Issuer's common stock in excess of 9.99%."},{"field":"shares","element":"transactionShares","label":"F1","text":"On March 11, 2020, each of Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Life Sciences Entities\") entered into a letter agreement with the Issuer that provides the Bain Life Sciences Entities with the right, on one occasion, to exchange all or any portion of the warrants to purchase an aggregate of 2,916,250 shares of the Issuer's common stock (each, a \"Warrant\") owned by the Bain Life Sciences Entities for one or more warrants (each, a \"Preferred Warrant\") to purchase shares of the Issuer's non-voting Series C Convertible Preferred Stock (the \"Series C Preferred Stock\").  Each share of Series C Preferred Stock will be convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock."},{"field":"shares","element":"transactionShares","label":"F2","text":"(Continued from footnote 1) Each Preferred Warrant issued in exchange for a Warrant will have an exercise price of $4,500 per share of Series C Preferred Stock and will be exercisable for a number of shares of Series C Preferred Stock equal to (x) the number of shares of Common Stock for which the Warrant then remains exercisable, divided by (y) 1,000.  The Warrants, the Series C Preferred Stock and the Series B Convertible Preferred Stock held by the Bain Life Sciences Entities each include provisions prohibiting exercise or conversion into the Issuer's common stock to the extent such exercise or conversion would result in beneficial ownership of the Issuer's common stock in excess of 9.99%."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F1","text":"On March 11, 2020, each of Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Life Sciences Entities\") entered into a letter agreement with the Issuer that provides the Bain Life Sciences Entities with the right, on one occasion, to exchange all or any portion of the warrants to purchase an aggregate of 2,916,250 shares of the Issuer's common stock (each, a \"Warrant\") owned by the Bain Life Sciences Entities for one or more warrants (each, a \"Preferred Warrant\") to purchase shares of the Issuer's non-voting Series C Convertible Preferred Stock (the \"Series C Preferred Stock\").  Each share of Series C Preferred Stock will be convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock."},{"field":"derivative.underlying_shares","element":"underlyingSecurityShares","label":"F2","text":"(Continued from footnote 1) Each Preferred Warrant issued in exchange for a Warrant will have an exercise price of $4,500 per share of Series C Preferred Stock and will be exercisable for a number of shares of Series C Preferred Stock equal to (x) the number of shares of Common Stock for which the Warrant then remains exercisable, divided by (y) 1,000.  The Warrants, the Series C Preferred Stock and the Series B Convertible Preferred Stock held by the Bain Life Sciences Entities each include provisions prohibiting exercise or conversion into the Issuer's common stock to the extent such exercise or conversion would result in beneficial ownership of the Issuer's common stock in excess of 9.99%."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F1","text":"On March 11, 2020, each of Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Life Sciences Entities\") entered into a letter agreement with the Issuer that provides the Bain Life Sciences Entities with the right, on one occasion, to exchange all or any portion of the warrants to purchase an aggregate of 2,916,250 shares of the Issuer's common stock (each, a \"Warrant\") owned by the Bain Life Sciences Entities for one or more warrants (each, a \"Preferred Warrant\") to purchase shares of the Issuer's non-voting Series C Convertible Preferred Stock (the \"Series C Preferred Stock\").  Each share of Series C Preferred Stock will be convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"(Continued from footnote 1) Each Preferred Warrant issued in exchange for a Warrant will have an exercise price of $4,500 per share of Series C Preferred Stock and will be exercisable for a number of shares of Series C Preferred Stock equal to (x) the number of shares of Common Stock for which the Warrant then remains exercisable, divided by (y) 1,000.  The Warrants, the Series C Preferred Stock and the Series B Convertible Preferred Stock held by the Bain Life Sciences Entities each include provisions prohibiting exercise or conversion into the Issuer's common stock to the extent such exercise or conversion would result in beneficial ownership of the Issuer's common stock in excess of 9.99%."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"On March 11, 2020, each of Bain Capital Life Sciences Fund, L.P. (\"BCLS\") and BCIP Life Sciences Associates, LP (\"BCIPLS\" and, together with BCLS, the \"Bain Life Sciences Entities\") entered into a letter agreement with the Issuer that provides the Bain Life Sciences Entities with the right, on one occasion, to exchange all or any portion of the warrants to purchase an aggregate of 2,916,250 shares of the Issuer's common stock (each, a \"Warrant\") owned by the Bain Life Sciences Entities for one or more warrants (each, a \"Preferred Warrant\") to purchase shares of the Issuer's non-voting Series C Convertible Preferred Stock (the \"Series C Preferred Stock\").  Each share of Series C Preferred Stock will be convertible, at the option of the holder, into 1,000 shares of the Issuer's common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"(Continued from footnote 1) Each Preferred Warrant issued in exchange for a Warrant will have an exercise price of $4,500 per share of Series C Preferred Stock and will be exercisable for a number of shares of Series C Preferred Stock equal to (x) the number of shares of Common Stock for which the Warrant then remains exercisable, divided by (y) 1,000.  The Warrants, the Series C Preferred Stock and the Series B Convertible Preferred Stock held by the Bain Life Sciences Entities each include provisions prohibiting exercise or conversion into the Issuer's common stock to the extent such exercise or conversion would result in beneficial ownership of the Issuer's common stock in excess of 9.99%."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"Bain Capital Life Sciences Investors, LLC (\"BCLSI\") is the ultimate general partner of BCLS, and governs the investment strategy and decision-making process with respect to investments held by BCIPLS.  Dr. Hack is a Managing Director of BCLSI.  By virtue of the relationships described in this footnote, Dr. Hack may be deemed to share voting and dispositive power with respect to the securities held by the Bain Life Sciences Entities.  Dr. Hack disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein."}],"balance_after":1,"derivative":{"exercise_date":"2020-03-11","expiration_date":"2022-02-12","underlying":"Preferred Warrants(Right to Buy)","underlying_shares":2916.25},"source":{"system":"sec-edgar","filing":"0000899243-20-008067","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924320008067/doc4.xml","form_type":"4"}},{"id":3438995,"issuer":{"id":66930,"kind":"organization","name":"DYNAVAX TECHNOLOGIES CORP","symbol":"DVAX"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. F.","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Option (Right to Buy)","published_at":"2019-08-14T18:17:29.000Z","date":"2019-08-12","kind":"grant","acquired":true,"shares":15000,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F2","text":"Not applicable."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option grant will vest over three years in equal installments on the anniversary of the grant date."}],"balance_after":15000,"derivative":{"exercise_price":3.36,"expiration_date":"2026-08-11","underlying":"Common Stock","underlying_shares":15000},"source":{"system":"sec-edgar","filing":"0000899243-19-021741","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1029142/000089924319021741/doc4.xml","form_type":"4"}},{"id":3494085,"issuer":{"id":69982,"kind":"organization","name":"Mersana Therapeutics, Inc.","symbol":"MRSN"},"owners":[{"id":69988,"kind":"person","name":"Hack Andrew A. F.","position":1,"cik":"0001657434","reported_name":"Hack Andrew A. 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