<SEC-DOCUMENT>0001193125-26-010883.txt : 20260112
<SEC-HEADER>0001193125-26-010883.hdr.sgml : 20260112
<ACCEPTANCE-DATETIME>20260112212630
ACCESSION NUMBER:		0001193125-26-010883
CONFORMED SUBMISSION TYPE:	144
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20260112
DATE AS OF CHANGE:		20260112

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Atara Biotherapeutics, Inc.
		CENTRAL INDEX KEY:			0001604464
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				460920988
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	001-36548
		FILM NUMBER:		26528281

	BUSINESS ADDRESS:	
		STREET 1:		1280 RANCHO CONEJO BLVD
		CITY:			THOUSAND OAKS
		STATE:			CA
		ZIP:			91320
		BUSINESS PHONE:		805-623-4211

	MAIL ADDRESS:	
		STREET 1:		1280 RANCHO CONEJO BLVD
		CITY:			THOUSAND OAKS
		STATE:			CA
		ZIP:			91320

REPORTING-OWNER:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Panacea Innovation Ltd
		CENTRAL INDEX KEY:			0002010692
		ORGANIZATION NAME:           	
		EIN:				000000000
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		144

	BUSINESS ADDRESS:	
		STREET 1:		C/O MAPLES CORPORATE SERVICES LIMITED
		STREET 2:		BOX 309, UGLAND HOUSE
		CITY:			GRAND CAYMAN
		STATE:			E9
		ZIP:			KY1-1104
		BUSINESS PHONE:		86 21 60252100

	MAIL ADDRESS:	
		STREET 1:		C/O MAPLES CORPORATE SERVICES LIMITED
		STREET 2:		BOX 309, UGLAND HOUSE
		CITY:			GRAND CAYMAN
		STATE:			E9
		ZIP:			KY1-1104
</SEC-HEADER>
<DOCUMENT>
<TYPE>144
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<headerData>
<submissionType>144</submissionType>
<filerInfo>
<filer>
<filerCredentials>
<cik>0002010692</cik>
<ccc>XXXXXXXX</ccc>
</filerCredentials>
</filer>
<liveTestFlag>LIVE</liveTestFlag>
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<formData>
<issuerInfo>
<issuerCik>0001604464</issuerCik>
<issuerName>Atara Biotherapeutics, Inc.</issuerName>
<secFileNumber>001-36548</secFileNumber>
<issuerAddress>
<street1 xmlns="http://www.sec.gov/edgar/common">1280 RANCHO CONEJO BLVD</street1>
<city xmlns="http://www.sec.gov/edgar/common">THOUSAND OAKS</city>
<stateOrCountry xmlns="http://www.sec.gov/edgar/common">CA</stateOrCountry>
<zipCode xmlns="http://www.sec.gov/edgar/common">91320</zipCode>
</issuerAddress>
<issuerContactPhone>805-623-4211</issuerContactPhone>
<nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Panacea Innovation Ltd</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
<relationshipsToIssuer>
<relationshipToIssuer>10% Stockholder</relationshipToIssuer>
</relationshipsToIssuer>
</issuerInfo>
<securitiesInformation>
<securitiesClassTitle>Common Stock</securitiesClassTitle>
<brokerOrMarketmakerDetails>
<name>Cantor Fitzgerald</name>
<address>
<street1 xmlns="http://www.sec.gov/edgar/common">110 East 59th Street</street1>
<city xmlns="http://www.sec.gov/edgar/common">NY</city>
<stateOrCountry xmlns="http://www.sec.gov/edgar/common">NY</stateOrCountry>
<zipCode xmlns="http://www.sec.gov/edgar/common">10022</zipCode>
</address>
</brokerOrMarketmakerDetails>
<noOfUnitsSold>40000</noOfUnitsSold>
<aggregateMarketValue>235200</aggregateMarketValue>
<noOfUnitsOutstanding>7210235</noOfUnitsOutstanding>
<approxSaleDate>01/12/2026</approxSaleDate>
<securitiesExchangeName>NASDAQ</securitiesExchangeName>
</securitiesInformation>
<securitiesInformation>
<securitiesClassTitle>Common Stock</securitiesClassTitle>
<brokerOrMarketmakerDetails>
<name>Jefferies</name>
<address>
<street1 xmlns="http://www.sec.gov/edgar/common">520 Madison Avenue</street1>
<city xmlns="http://www.sec.gov/edgar/common">NY</city>
<stateOrCountry xmlns="http://www.sec.gov/edgar/common">NY</stateOrCountry>
<zipCode xmlns="http://www.sec.gov/edgar/common">10022</zipCode>
</address>
</brokerOrMarketmakerDetails>
<noOfUnitsSold>20000</noOfUnitsSold>
<aggregateMarketValue>117600.00</aggregateMarketValue>
<noOfUnitsOutstanding>7210235</noOfUnitsOutstanding>
<approxSaleDate>01/12/2026</approxSaleDate>
<securitiesExchangeName>NASDAQ</securitiesExchangeName>
</securitiesInformation>
<securitiesInformation>
<securitiesClassTitle>Common Stock</securitiesClassTitle>
<brokerOrMarketmakerDetails>
<name>JP Morgan</name>
<address>
<street1 xmlns="http://www.sec.gov/edgar/common">270 Park Avenue</street1>
<city xmlns="http://www.sec.gov/edgar/common">NY</city>
<stateOrCountry xmlns="http://www.sec.gov/edgar/common">NY</stateOrCountry>
<zipCode xmlns="http://www.sec.gov/edgar/common">10017</zipCode>
</address>
</brokerOrMarketmakerDetails>
<noOfUnitsSold>20554</noOfUnitsSold>
<aggregateMarketValue>120858.00</aggregateMarketValue>
<noOfUnitsOutstanding>7210235</noOfUnitsOutstanding>
<approxSaleDate>01/12/2026</approxSaleDate>
<securitiesExchangeName>NASDAQ</securitiesExchangeName>
</securitiesInformation>
<securitiesToBeSold>
<securitiesClassTitle>Common Stock</securitiesClassTitle>
<acquiredDate>08/15/2025</acquiredDate>
<natureOfAcquisitionTransaction>The Common Stock was purchased in multiple open market transactions  from January 2025 through August  2025 as well as a registered direct financing in May 2025.</natureOfAcquisitionTransaction>
<nameOfPersonfromWhomAcquired>Brokerage transactions</nameOfPersonfromWhomAcquired>
<isGiftTransaction>N</isGiftTransaction>
<amountOfSecuritiesAcquired>1405000</amountOfSecuritiesAcquired>
<paymentDate>08/15/2025</paymentDate>
<natureOfPayment>Cash</natureOfPayment>
</securitiesToBeSold>
<nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
<remarks>The shares that are sold are held of record by Panacea Venture Healthcare Fund II, L.P.</remarks>
<noticeSignature>
<noticeDate>01/12/2026</noticeDate>
<signature>/s/ James Huang, Founding Managing Partner</signature>
</noticeSignature>
</formData>
</edgarSubmission>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
