{"transactions":[{"id":784381,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-05-11T22:45:04.000Z","date":"2026-05-07","kind":"sale","planned":false,"acquired":false,"shares":313446,"price":10.0975,"value":3165020.985,"ownership":{"direct":false,"nature":"See Footnote"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $10.00 to $10.50, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder of the Issuer, 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 above."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Represents securities held by Panacea Venture Healthcare Fund II, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":1011000,"source":{"system":"sec-edgar","filing":"0001193125-26-217380","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312526217380/ownership.xml","form_type":"4"}},{"id":833171,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Warrants","published_at":"2026-03-19T20:30:10.000Z","date":"2026-03-17","kind":"exercise","planned":false,"acquired":false,"shares":259163,"price":6.6099,"value":1713041.5137,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":0,"derivative":{"exercise_price":0.0001,"underlying":"Common Stock","underlying_shares":259163},"source":{"system":"sec-edgar","filing":"0001193125-26-116060","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312526116060/ownership.xml","form_type":"4"}},{"id":833170,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-03-19T20:30:10.000Z","date":"2026-03-17","kind":"tax_withholding","planned":false,"acquired":false,"shares":5,"price":5.23,"value":26.15,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":307894,"source":{"system":"sec-edgar","filing":"0001193125-26-116060","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312526116060/ownership.xml","form_type":"4"}},{"id":833169,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-03-19T20:30:10.000Z","date":"2026-03-17","kind":"exercise","planned":false,"acquired":true,"shares":259163,"price":0.0001,"value":25.9163,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":307899,"source":{"system":"sec-edgar","filing":"0001193125-26-116060","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312526116060/ownership.xml","form_type":"4"}},{"id":939081,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2026-01-15T02:16:25.000Z","date":"2026-01-12","kind":"sale","planned":false,"acquired":false,"shares":80554,"price":6.0707,"value":489019.1678,"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 ranging from $5.9888 to $6.2838, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder of the Issuer, 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 above."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Venture Healthcare Fund II, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":1324446,"source":{"system":"sec-edgar","filing":"0001193125-26-013358","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312526013358/ownership.xml","form_type":"4"}},{"id":984839,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Warrants","published_at":"2025-12-01T22:00:04.000Z","date":"2025-11-28","kind":"exercise","planned":false,"acquired":false,"shares":48737,"price":6.6099,"value":322146.6963,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"derivative.exercise_date","element":"exerciseDate","label":"F4","text":"The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F4","text":"The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F4","text":"The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":259163,"derivative":{"exercise_price":0.0001,"underlying":"Common Stock","underlying_shares":48737},"source":{"system":"sec-edgar","filing":"0001193125-25-304018","document":"ownership.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312525304018/ownership.xml","form_type":"4"}},{"id":984838,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-12-01T22:00:04.000Z","date":"2025-11-28","kind":"tax_withholding","planned":false,"acquired":false,"shares":1,"price":14.03,"value":14.03,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":48736,"source":{"system":"sec-edgar","filing":"0001193125-25-304018","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312525304018/ownership.xml","form_type":"4"}},{"id":984837,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-12-01T22:00:04.000Z","date":"2025-11-28","kind":"exercise","planned":false,"acquired":true,"shares":48737,"price":0.0001,"value":4.8737,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Opportunity Fund I, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":48737,"source":{"system":"sec-edgar","filing":"0001193125-25-304018","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000119312525304018/ownership.xml","form_type":"4"}},{"id":1061285,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-08-20T00:15:04.000Z","date":"2025-08-15","kind":"purchase","planned":false,"acquired":true,"shares":55000,"price":12.1895,"value":670422.5,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions ranging from $11.83 to $12.44, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder of the Issuer, 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 above."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"Represents securities held by Panacea Venture Healthcare Fund II, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F3","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":1405000,"source":{"system":"sec-edgar","filing":"0000950170-25-110310","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000095017025110310/ownership.xml","form_type":"4"}},{"id":1083922,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":48282,"kind":"organization","name":"Panacea Innovation Ltd","position":1,"cik":"0002010692","reported_name":"Panacea Innovation Ltd","relationship":{"director":false,"officer":false,"ten_percent_owner":true,"other":false}},{"id":42283,"kind":"person","name":"Huang James","position":2,"cik":"0001573160","reported_name":"Huang James","relationship":{"director":true,"officer":false,"ten_percent_owner":true,"other":false}}],"security":"Common Stock","published_at":"2025-07-21T13:00:05.000Z","date":"2025-07-17","kind":"purchase","planned":false,"acquired":true,"shares":19335,"price":9.6391,"value":186371.9985,"ownership":{"direct":false,"nature":"See Footnotes"},"footnotes":[{"field":"ownership.nature","element":"natureOfOwnership","label":"F1","text":"Represents securities held by Panacea Venture Healthcare Fund II, L.P."},{"field":"ownership.nature","element":"natureOfOwnership","label":"F2","text":"James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. (\"Fund II GP\") and Panacea Opportunity Fund I GP Company, Ltd. (\"Opportunity Fund GP\"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership."}],"balance_after":1350000,"source":{"system":"sec-edgar","filing":"0000950170-25-097087","document":"ownership.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1573160/000095017025097087/ownership.xml","form_type":"4"}}]}