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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":269938,"source":{"system":"sec-edgar","filing":"0001209191-17-010165","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919117010165/doc4.xml","form_type":"4"}},{"id":4461566,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EVP & Chief Strategy Officer"}}],"security":"Common Stock","published_at":"2017-02-08T17:36:39.000Z","date":"2017-02-06","kind":"grant","acquired":true,"shares":45000,"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":275812,"source":{"system":"sec-edgar","filing":"0001209191-17-008824","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919117008824/doc4.xml","form_type":"4"}},{"id":4545055,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-11-22T17:31:48.000Z","date":"2016-11-17","kind":"sale","acquired":false,"shares":1480,"price":18.41,"value":27246.8,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Transaction pursuant to Rule 10b5-1 Plan adopted September 26, 2016."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price in Column 4 is a weighted average sale price. The prices actually received ranged from $18.10 to $18.85. 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":230812,"source":{"system":"sec-edgar","filing":"0001209191-16-151759","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116151759/doc4.xml","form_type":"4"}},{"id":4552942,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Restricted Stock Units","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-15","kind":"exercise","acquired":false,"shares":4146,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F6","text":"Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock or a cash settlement."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F9","text":"The RSUs were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's initial public offering (the \"IPO\"). The shares that vested on the closing date of the IPO, and the shares that vested thereafter through May 15, 2015, were settled on May 15, 2015. The service-based vesting condition provides that 1/48th of the total number of shares shall vest monthly from January 10, 2014, subject to the holder's continuous service through each such date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F10","text":"The earlier of (i) January 10, 2021 or (ii) the recipient's termination date."}],"balance_after":19347,"derivative":{"underlying":"Common Stock","underlying_shares":4146},"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":6,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4552941,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Restricted Stock Units","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-15","kind":"exercise","acquired":false,"shares":9615,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F6","text":"Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock or a cash settlement."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F7","text":"The RSUs were granted with both (a) a liquidity event-based vesting condition and (b) a service-based vesting condition, both of which conditions must be satisfied in order for the RSUs to vest. The liquidity event-based condition was satisfied upon the closing of the Issuer's initial public offering (the \"IPO\"). The shares that vested on the closing date of the IPO, and the shares that vested thereafter through May 15, 2015, were settled on May 15, 2015. The service-based vesting condition provides that 25% of the total number of shares on March 25, 2014 and 1/48th of the total number of shares monthly thereafter, subject to the holder's continuous service through each such date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F8","text":"The earlier of (i) March 13, 2020 or (ii) the recipient's termination date."}],"balance_after":16026,"derivative":{"underlying":"Common Stock","underlying_shares":9615},"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4552940,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-16","kind":"sale","acquired":false,"shares":7136,"price":19.27,"value":137510.72,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Transaction pursuant to Rule 10b5-1 Plan adopted September 26, 2016."},{"field":"kind","element":"transactionCoding","label":"F4","text":"Shares sold to cover tax liability from settlement of RSUs."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price in Column 4 is a weighted average sale price. The prices actually received ranged from $18.80 to $19.55. 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":232292,"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4552939,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-15","kind":"exercise","acquired":true,"shares":4146,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Shares issued upon settlement of vested restricted stock units (\"RSUs\")."}],"balance_after":239428,"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4552938,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-15","kind":"exercise","acquired":true,"shares":9615,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F3","text":"Shares issued upon settlement of vested restricted stock units (\"RSUs\")."}],"balance_after":235282,"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4552937,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-11-16T20:17:09.000Z","date":"2016-11-14","kind":"sale","acquired":false,"shares":9582,"price":20.55,"value":196910.1,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"Transaction pursuant to Rule 10b5-1 Plan adopted September 26, 2016."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price in Column 4 is a weighted average sale price. The prices actually received ranged from $20.15 to $21.05. 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":225667,"source":{"system":"sec-edgar","filing":"0001209191-16-150727","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116150727/doc4.xml","form_type":"4"}},{"id":4596399,"issuer":{"id":6828,"kind":"organization","name":"Atara Biotherapeutics, Inc.","symbol":"ATRA"},"owners":[{"id":75431,"kind":"person","name":"Soffer Gad","position":1,"cik":"0001612090","reported_name":"Soffer Gad","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Operating Officer"}}],"security":"Common Stock","published_at":"2016-09-23T19:25:52.000Z","date":"2016-09-22","kind":"grant","acquired":true,"shares":90000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"These restricted stock units vest over 4 years, 50% on the 2nd anniversary of the grant date of September 22, 2016 and 25% on the anniversary of the grant date of September 22, 2016 in each of the following years."}],"balance_after":235249,"source":{"system":"sec-edgar","filing":"0001209191-16-142707","document":"doc4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1612090/000120919116142707/doc4.xml","form_type":"4"}}]}