{"transactions":[{"id":725220,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2026-06-26T20:31:14.000Z","date":"2026-06-24","kind":"grant","planned":false,"acquired":true,"shares":62000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option shall vest and become exercisable in full upon the earlier to occur of (i) June 24, 2027 and (ii) the next annual meeting of the Issuer's stockholders, subject to the recipient's continued service as a member of the Board on such date."}],"balance_after":62000,"derivative":{"exercise_price":4.25,"expiration_date":"2036-06-23","underlying":"Common Stock","underlying_shares":62000},"source":{"system":"sec-edgar","filing":"0001470831-26-000667","document":"wk-form4_1782505872.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000147083126000667/wk-form4_1782505872.xml","form_type":"4"}},{"id":1104575,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2025-06-20T20:12:00.000Z","date":"2025-06-18","kind":"grant","planned":false,"acquired":true,"shares":35500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option shall vest and become exercisable in full upon the earlier to occur of (i) June 18, 2026 and (ii) the next annual meeting of the Issuer's stockholders, subject to the recipient's continued service as a member of the Board on such date."}],"balance_after":35500,"derivative":{"exercise_price":1.44,"expiration_date":"2035-06-17","underlying":"Common Stock","underlying_shares":35500},"source":{"system":"sec-edgar","filing":"0001662579-25-000049","document":"wk-form4_1750450313.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000166257925000049/wk-form4_1750450313.xml","form_type":"4"}},{"id":1471669,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2024-06-21T20:08:19.000Z","date":"2024-06-20","kind":"grant","planned":false,"acquired":true,"shares":32500,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option shall vest and become exercisable in full upon the earlier to occur of (i) June 20, 2025 and (ii) the next annual meeting of the Issuer's stockholders, subject to the recipient's continued service as a member of the Board on such date."}],"balance_after":32500,"derivative":{"exercise_price":4.05,"expiration_date":"2034-06-19","underlying":"Common Stock","underlying_shares":32500},"source":{"system":"sec-edgar","filing":"0001662579-24-000058","document":"wk-form4_1719000491.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000166257924000058/wk-form4_1719000491.xml","form_type":"4"}},{"id":1851287,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2023-06-16T20:22:37.000Z","date":"2023-06-15","kind":"grant","planned":false,"acquired":true,"shares":26000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"This option shall vest and become exercisable in full upon the earlier to occur of (i) June 15, 2024 and (ii) the next annual meeting of the Issuer's stockholders, subject to the recipient's continued service as a member of the Board on such date."}],"balance_after":26000,"derivative":{"exercise_price":3.61,"expiration_date":"2033-06-14","underlying":"Common Stock","underlying_shares":26000},"source":{"system":"sec-edgar","filing":"0001662579-23-000057","document":"wk-form4_1686946946.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000166257923000057/wk-form4_1686946946.xml","form_type":"4"}},{"id":1968223,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2023-03-06T23:47:31.000Z","date":"2023-03-02","kind":"sale","acquired":false,"shares":6871,"price":3.627,"value":24921.117,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2023 and March 3, 2023 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":181978,"source":{"system":"sec-edgar","filing":"0001567619-23-004538","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761923004538/doc1.xml","form_type":"4"}},{"id":2022155,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Common Stock","published_at":"2023-02-10T21:27:22.000Z","date":"2023-02-08","kind":"purchase","acquired":true,"shares":5667,"price":5.6,"value":31735.2,"ownership":{"direct":true},"balance_after":5667,"source":{"system":"sec-edgar","filing":"0001662579-23-000027","document":"wf-form4_167606442384071.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000166257923000027/wf-form4_167606442384071.xml","form_type":"4"}},{"id":2024340,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2023-02-09T22:00:12.000Z","date":"2023-02-07","kind":"sale","acquired":false,"shares":2485,"price":5.46,"value":13568.1,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."}],"balance_after":188849,"source":{"system":"sec-edgar","filing":"0001567619-23-002174","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761923002174/doc1.xml","form_type":"4"}},{"id":2109938,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-11-19T01:13:28.000Z","date":"2022-11-16","kind":"sale","acquired":false,"shares":1083,"price":4.491,"value":4863.753,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 16, 2022 and November 17, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":191334,"source":{"system":"sec-edgar","filing":"0001140361-22-042378","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122042378/form4.xml","form_type":"4"}},{"id":2109937,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-11-19T01:13:28.000Z","date":"2022-11-16","kind":"sale","acquired":false,"shares":5172,"price":4.49,"value":23222.28,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 16, 2022 and November 17, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":192417,"source":{"system":"sec-edgar","filing":"0001140361-22-042378","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122042378/form4.xml","form_type":"4"}},{"id":2179086,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-08-18T22:20:26.000Z","date":"2022-08-16","kind":"sale","acquired":false,"shares":5940,"price":5.035,"value":29907.9,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 16, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":197589,"source":{"system":"sec-edgar","filing":"0001140361-22-030297","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122030297/form4.xml","form_type":"4"}},{"id":2235343,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-06-10T20:20:41.000Z","date":"2022-06-08","kind":"sale","acquired":false,"shares":5853,"price":5.63,"value":32952.39,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 1,790 shares purchased under the Issuer's Employee Stock Purchase Plan on May 31, 2022."}],"balance_after":203529,"source":{"system":"sec-edgar","filing":"0001567619-22-012667","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761922012667/doc1.xml","form_type":"4"}},{"id":2263119,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-05-19T21:16:11.000Z","date":"2022-05-17","kind":"sale","acquired":false,"shares":966,"price":5.317,"value":5136.222,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on May 17, 2022 and May 18, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":207592,"source":{"system":"sec-edgar","filing":"0001140361-22-019988","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122019988/form4.xml","form_type":"4"}},{"id":2263118,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-05-19T21:16:11.000Z","date":"2022-05-17","kind":"sale","acquired":false,"shares":4616,"price":5.316,"value":24538.656,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on May 17, 2022 and May 18, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":208558,"source":{"system":"sec-edgar","filing":"0001140361-22-019988","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122019988/form4.xml","form_type":"4"}},{"id":2326108,"issuer":{"id":5503,"kind":"organization","name":"C4 Therapeutics, Inc.","symbol":"CCCC"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock Option (Right to Buy)","published_at":"2022-03-17T20:20:49.000Z","date":"2022-03-16","kind":"grant","acquired":true,"shares":41200,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"33% of the shares underlying this option shall vest and become exercisable on March 16, 2023, with the remainder vesting in eight equal quarterly installments thereafter."}],"balance_after":41200,"derivative":{"exercise_price":22.64,"expiration_date":"2032-03-15","underlying":"Common Stock","underlying_shares":41200},"source":{"system":"sec-edgar","filing":"0001209191-22-019573","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1662579/000120919122019573/doc4.xml","form_type":"4"}},{"id":2352705,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2022-03-04T00:02:45.000Z","date":"2022-03-01","kind":"grant","acquired":true,"shares":115107,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"1/48th of the shares subject to the stock option vest and become exercisable each month with the initial installment vesting on April 1, 2022, subject to the reporting person's continuous service."}],"balance_after":115107,"derivative":{"exercise_price":10.21,"expiration_date":"2032-02-28","underlying":"Common Stock","underlying_shares":115107},"source":{"system":"sec-edgar","filing":"0001140361-22-007767","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122007767/form4.xml","form_type":"4"}},{"id":2352704,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-03-04T00:02:45.000Z","date":"2022-03-01","kind":"sale","acquired":false,"shares":1491,"price":9.857,"value":14696.787,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F2","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 1, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":213174,"source":{"system":"sec-edgar","filing":"0001140361-22-007767","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122007767/form4.xml","form_type":"4"}},{"id":2352703,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-03-04T00:02:45.000Z","date":"2022-03-01","kind":"sale","acquired":false,"shares":2272,"price":9.856,"value":22392.832,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F2","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted restricted stock units."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 1, 2022 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employee."}],"balance_after":214665,"source":{"system":"sec-edgar","filing":"0001140361-22-007767","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122007767/form4.xml","form_type":"4"}},{"id":2352702,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-03-04T00:02:45.000Z","date":"2022-03-01","kind":"grant","acquired":true,"shares":61235,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest in 16 equal quarterly installments on each Company Quarterly Vesting Date (as defined below), with the initial installment vesting on May 15, 2022, subject to the reporting person's continuous service. Company Quarterly Vesting Date means March 1, May 15, August 15 and November 15 of each year."}],"balance_after":216937,"source":{"system":"sec-edgar","filing":"0001140361-22-007767","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000114036122007767/form4.xml","form_type":"4"}},{"id":2405846,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2022-02-09T21:35:20.000Z","date":"2022-02-07","kind":"sale","acquired":false,"shares":2496,"price":14.4615,"value":36095.904,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on February 7, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees. The prices actually received ranged from $14.46 to $14.75, inclusive. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold on behalf of the group at each price within the range."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 484 shares purchased under the Issuer's Employee Stock Purchase Plan on November 30, 2021."}],"balance_after":155702,"source":{"system":"sec-edgar","filing":"0001567619-22-003052","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761922003052/doc1.xml","form_type":"4"}},{"id":2502625,"issuer":{"id":16545,"kind":"organization","name":"Flexion Therapeutics Inc","symbol":"FLXN"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock option (right to buy)","published_at":"2021-11-19T10:13:44.000Z","date":"2021-11-19","kind":"disposition_to_issuer","acquired":false,"shares":32000,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Pursuant to the Agreement and Plan of Merger, dated as of October 11, 2021, by and among Flexion Therapeutics, Inc. (\"Issuer\"), Pacira BioSciences, Inc. and Oyster Acquisition Company Inc. (\"Purchaser\") (\"Merger Agreement\"), on November 19, 2021, Purchaser merged with and into Issuer, with Issuer continuing as the surviving corporation (\"Merger\")."},{"field":"price","element":"transactionPricePerShare","label":"F1","text":"Pursuant to the Agreement and Plan of Merger, dated as of October 11, 2021, by and among Flexion Therapeutics, Inc. (\"Issuer\"), Pacira BioSciences, Inc. and Oyster Acquisition Company Inc. (\"Purchaser\") (\"Merger Agreement\"), on November 19, 2021, Purchaser merged with and into Issuer, with Issuer continuing as the surviving corporation (\"Merger\")."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"At the effective time of the Merger, each outstanding option with an exercise price less than $8.50 per share was accelerated and became fully vested and exercisable and was cancelled and converted into the right to receive (i) cash in an amount equal to the product of (a) the total number of shares of Issuer common stock subject to such option multiplied by (b) the excess of (x) $8.50 per share over (y) the exercise price payable per share of Issuer common stock under such option, and (ii) one non-transferable contractual contingent value right per share, which represent the right to receive one or more contingent payments of up to $8.00 per share in the aggregate, in cash, upon the achievement of specified milestones."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"Pursuant to the Agreement and Plan of Merger, dated as of October 11, 2021, by and among Flexion Therapeutics, Inc. (\"Issuer\"), Pacira BioSciences, Inc. and Oyster Acquisition Company Inc. (\"Purchaser\") (\"Merger Agreement\"), on November 19, 2021, Purchaser merged with and into Issuer, with Issuer continuing as the surviving corporation (\"Merger\")."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"At the effective time of the Merger, each outstanding option with an exercise price less than $8.50 per share was accelerated and became fully vested and exercisable and was cancelled and converted into the right to receive (i) cash in an amount equal to the product of (a) the total number of shares of Issuer common stock subject to such option multiplied by (b) the excess of (x) $8.50 per share over (y) the exercise price payable per share of Issuer common stock under such option, and (ii) one non-transferable contractual contingent value right per share, which represent the right to receive one or more contingent payments of up to $8.00 per share in the aggregate, in cash, upon the achievement of specified milestones."}],"balance_after":0,"derivative":{"exercise_price":7.82,"expiration_date":"2031-07-08","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001209191-21-065717","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1419600/000120919121065717/doc4.xml","form_type":"4"}},{"id":2504295,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-11-18T22:53:12.000Z","date":"2021-11-16","kind":"sale","acquired":false,"shares":3655,"price":17.1169,"value":62562.2695,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 16, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees. The prices actually received ranged from $16.45 to $17.3823. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold on behalf of the group at each price within the range."}],"balance_after":157714,"source":{"system":"sec-edgar","filing":"0001567619-21-020778","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761921020778/doc1.xml","form_type":"4"}},{"id":2595805,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-08-19T23:34:34.000Z","date":"2021-08-17","kind":"sale","acquired":false,"shares":3579,"price":12.532,"value":44852.028,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 17, 2021 and August 18, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."}],"balance_after":161369,"source":{"system":"sec-edgar","filing":"0001567619-21-016148","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761921016148/doc1.xml","form_type":"4"}},{"id":2636020,"issuer":{"id":16545,"kind":"organization","name":"Flexion Therapeutics Inc","symbol":"FLXN"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":true,"officer":false,"ten_percent_owner":false,"other":false}}],"security":"Stock option (right to buy)","published_at":"2021-07-12T16:06:15.000Z","date":"2021-07-09","kind":"grant","acquired":true,"shares":32000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F1","text":"One-third of the shares subject to the option will vest on July 9, 2022, and the balance of the shares will vest in a series of 24 equal monthly installments thereafter."}],"balance_after":32000,"derivative":{"exercise_price":7.82,"expiration_date":"2031-07-08","underlying":"Common Stock","underlying_shares":32000},"source":{"system":"sec-edgar","filing":"0001209191-21-046289","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1419600/000120919121046289/doc4.xml","form_type":"4"}},{"id":2675042,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-06-09T20:06:44.000Z","date":"2021-06-08","kind":"sale","acquired":false,"shares":5820,"price":14.06,"value":81829.2,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 1,802 shares issued on May 28, 2021 pursuant to the Issuer's Employee Stock Purchase Plan."}],"balance_after":164948,"source":{"system":"sec-edgar","filing":"0001567619-21-011898","document":"doc1.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000156761921011898/doc1.xml","form_type":"4"}},{"id":2702484,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-05-20T20:30:44.000Z","date":"2021-05-18","kind":"sale","acquired":false,"shares":3616,"price":14.55,"value":52612.8,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on May 18, 2021 and May 19, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."}],"balance_after":168966,"source":{"system":"sec-edgar","filing":"0001209191-21-034424","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121034424/doc4.xml","form_type":"4"}},{"id":2767554,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-03-30T21:19:37.000Z","date":"2021-03-26","kind":"sale","acquired":false,"shares":1761,"price":14.58,"value":25675.38,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the reporting person. The sale is intended to comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act and be interpreted to meet the requirements of Rule 10b5-1(c)."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price in Column 4 is a weighted average sale price. The prices actually received ranged from $14.58 to $14.61. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range."}],"balance_after":172582,"source":{"system":"sec-edgar","filing":"0001209191-21-023586","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121023586/doc4.xml","form_type":"4"}},{"id":2808077,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-03-04T21:07:14.000Z","date":"2021-03-02","kind":"sale","acquired":false,"shares":1461,"price":16.74,"value":24457.14,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2021 and March 3, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."}],"balance_after":174343,"source":{"system":"sec-edgar","filing":"0001209191-21-017770","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121017770/doc4.xml","form_type":"4"}},{"id":2811297,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2021-03-03T22:14:08.000Z","date":"2021-03-01","kind":"grant","acquired":true,"shares":68314,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"1/48th of the shares subject to the stock option vest and become exercisable each month with the initial installment vesting on April 1, 2021, subject to the reporting person's continuous service."}],"balance_after":68314,"derivative":{"exercise_price":17.105,"expiration_date":"2031-02-28","underlying":"Common Stock","underlying_shares":68314},"source":{"system":"sec-edgar","filing":"0001209191-21-017033","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121017033/doc4.xml","form_type":"4"}},{"id":2811296,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-03-03T22:14:08.000Z","date":"2021-03-01","kind":"grant","acquired":true,"shares":45258,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest in 16 equal quarterly installments on each Company Quarterly Vesting Date (as defined below), with the initial installment vesting on May 15, 2021, subject to the reporting person's continuous service.  Company Quarterly Vesting Date means March 1, May 15, August 15 and November 15 of each year."}],"balance_after":175804,"source":{"system":"sec-edgar","filing":"0001209191-21-017033","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121017033/doc4.xml","form_type":"4"}},{"id":2871207,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2021-02-10T00:59:55.000Z","date":"2021-02-08","kind":"sale","acquired":false,"shares":1759,"price":20.39,"value":35866.01,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the reporting person. The sale is intended to comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act and be interpreted to meet the requirements of Rule 10b5-1(c)."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on February 8, 2021 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 244 shares issued pursuant to the Issuer's Employee Stock Purchase Plan on November 30, 2020."}],"balance_after":130546,"source":{"system":"sec-edgar","filing":"0001209191-21-009055","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919121009055/doc4.xml","form_type":"4"}},{"id":2974379,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-11-18T21:08:42.000Z","date":"2020-11-17","kind":"sale","acquired":false,"shares":1469,"price":19.774,"value":29048.006,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2020 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."}],"balance_after":132061,"source":{"system":"sec-edgar","filing":"0001209191-20-059047","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120059047/doc4.xml","form_type":"4"}},{"id":3050698,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-08-20T23:38:22.000Z","date":"2020-08-18","kind":"sale","acquired":false,"shares":1496,"price":12.09,"value":18086.64,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2020 and August 19, 2020 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."}],"balance_after":133530,"source":{"system":"sec-edgar","filing":"0001209191-20-047820","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120047820/doc4.xml","form_type":"4"}},{"id":3114279,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-06-10T20:05:40.000Z","date":"2020-06-09","kind":"sale","acquired":false,"shares":3924,"price":10.18,"value":39946.32,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 1,575 shares issued on May 29, 2020 pursuant to the Issuer's Employee Stock Purchase Plan."}],"balance_after":135026,"source":{"system":"sec-edgar","filing":"0001209191-20-035488","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120035488/doc4.xml","form_type":"4"}},{"id":3140355,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-05-20T22:11:16.000Z","date":"2020-05-18","kind":"sale","acquired":false,"shares":1428,"price":11.22,"value":16022.16,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Shares sold pursuant to a 10b5-1 arrangement to satisfy tax obligations in connection with the vesting of previously granted Restricted Stock Units."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on May 18, 2020 and May\n19, 2020 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 817 shares issued on May 31, 2019 and 656 shares issued on November 29, 2019 pursuant to the Issuer's Employee Stock Purchase Plan."}],"balance_after":137375,"source":{"system":"sec-edgar","filing":"0001209191-20-031005","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120031005/doc4.xml","form_type":"4"}},{"id":3191925,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-03-30T20:06:34.000Z","date":"2020-03-27","kind":"sale","acquired":false,"shares":1827,"price":9.17,"value":16753.59,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the reporting person. The sale is intended to comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act and be interpreted to meet the requirements of Rule 10b5-1(c)."}],"balance_after":137330,"source":{"system":"sec-edgar","filing":"0001209191-20-021699","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120021699/doc4.xml","form_type":"4"}},{"id":3230645,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2020-03-03T22:01:31.000Z","date":"2020-03-01","kind":"grant","acquired":true,"shares":73750,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"1/48th of the shares subject to the stock option vest and become exercisable each month with the initial installment vesting on April 1, 2020, subject to the reporting person's continuous service."}],"balance_after":73750,"derivative":{"exercise_price":12.15,"expiration_date":"2030-02-28","underlying":"Common Stock","underlying_shares":73750},"source":{"system":"sec-edgar","filing":"0001209191-20-015362","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120015362/doc4.xml","form_type":"4"}},{"id":3230644,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-03-03T22:01:31.000Z","date":"2020-03-01","kind":"grant","acquired":true,"shares":66875,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest in 16 equal quarterly installments on each Company Quarterly Vesting Date (as defined below), with the initial installment vesting on May 15, 2020, subject to the reporting person's continuous service.  Company Quarterly Vesting Date means March 1, May 15, August 15 and November 15 of each year."}],"balance_after":139157,"source":{"system":"sec-edgar","filing":"0001209191-20-015362","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120015362/doc4.xml","form_type":"4"}},{"id":3281572,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2020-02-11T00:47:44.000Z","date":"2020-02-06","kind":"sale","acquired":false,"shares":1781,"price":14.21,"value":25308.01,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a \"sell to cover\" transaction and does not represent a discretionary trade by the reporting person. The sale is intended to comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act and be interpreted to meet the requirements of Rule 10b5-1(c)."}],"balance_after":72282,"source":{"system":"sec-edgar","filing":"0001209191-20-008125","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919120008125/doc4.xml","form_type":"4"}},{"id":3576207,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2019-03-27T21:19:11.000Z","date":"2019-03-26","kind":"grant","acquired":true,"shares":10000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest as to 50% of the shares on March 26, 2020 and 50% of the shares on March 26, 2021, subject to the reporting\nperson's continuous service."}],"balance_after":74063,"source":{"system":"sec-edgar","filing":"0001209191-19-021445","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919119021445/doc4.xml","form_type":"4"}},{"id":3667584,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2019-02-08T21:44:11.000Z","date":"2019-02-06","kind":"grant","acquired":true,"shares":34125,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"1/48th of the shares subject to the stock option vest and become exercisable each month following February 6, 2019, subject to the reporting person's continuous service.."}],"balance_after":34125,"derivative":{"exercise_price":38.47,"expiration_date":"2029-02-05","underlying":"Common Stock","underlying_shares":34125},"source":{"system":"sec-edgar","filing":"0001209191-19-008568","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919119008568/doc4.xml","form_type":"4"}},{"id":3667583,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2019-02-08T21:44:11.000Z","date":"2019-02-06","kind":"grant","acquired":true,"shares":17063,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest in four equal annual installments on each of the first, second, third and fourth anniversaries of the grant date, subject to the reporting person's continuous service."}],"balance_after":64063,"source":{"system":"sec-edgar","filing":"0001209191-19-008568","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919119008568/doc4.xml","form_type":"4"}},{"id":3819209,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2018-09-11T22:49:12.000Z","date":"2018-07-27","kind":"purchase","acquired":true,"shares":2000,"price":36.8,"value":73600.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price in Column 4 is a weighted average purchase price. The prices actually paid ranged from $36.40 to $37.20. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares purchased at each price within the range."}],"balance_after":47000,"source":{"system":"sec-edgar","filing":"0001209191-18-050564","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919118050564/doc4.xml","form_type":"4"}},{"id":3901194,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2018-06-07T22:26:37.000Z","date":"2018-06-07","kind":"grant","acquired":true,"shares":75000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F2","text":"25% of the shares subject to the option vest on June 7, 2019 and the remaining shares vest in equal monthly installments over the following 36 months."}],"balance_after":75000,"derivative":{"exercise_price":42.3,"expiration_date":"2025-06-06","underlying":"Common Stock","underlying_shares":75000},"source":{"system":"sec-edgar","filing":"0001209191-18-036488","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919118036488/doc4.xml","form_type":"4"}},{"id":3901193,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":35088,"kind":"person","name":"Koppikar Utpal","position":1,"cik":"0001742696","reported_name":"Koppikar Utpal","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2018-06-07T22:26:37.000Z","date":"2018-06-07","kind":"grant","acquired":true,"shares":45000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"25% of the shares subject to restricted stock units vest on June 7, 2019 and the remaining shares vest in equal annual installments over the following 3 years."}],"balance_after":45000,"source":{"system":"sec-edgar","filing":"0001209191-18-036488","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1604464/000120919118036488/doc4.xml","form_type":"4"}}]}