ATARA BIOTHERAPEUTICS INC (ATRA) is held by 24 institutional investors that disclose positions via SEC 13F filings. The largest disclosed holder is ADAGE CAPITAL PARTNERS GP, L.L.C. as of Q1 2026.

Are institutions buying or selling ATRA?

In Q1 2026, 14 institutions opened or increased positions in ATARA BIOTHERAPEUTICS INC while 12 reduced or exited — a net buying quarter.

What is the Smart Money Verdict on ATRA?

The Smart Money Verdict combines four independent sources (institutional 13F activity, insider trades, activist filings, and congressional trades) into a single assessment for ATARA BIOTHERAPEUTICS INC.

How many hedge funds hold ATRA?

24 institutional investors report holding ATARA BIOTHERAPEUTICS INC (ATRA) as of Q1 2026, based on SEC 13F filings.

Is institutional money flowing into ATRA?

As of Q1 2026, tracked institutions in ATARA BIOTHERAPEUTICS INC show 14 buyers versus 12 sellers — net inflows.

ATARA BIOTHERAPEUTICS INC

ATRA·046513206·US·Common Stock·Healthcare - Biotechnology-Activist

Holders

Avg rating(6 Elite)

$8.5M

Total Value

54% (34)

Fund Consensus

14 buying - 12 selling

Smart Money Verdict

View all

Held by 24 funds

6 elite

Who's Trading

ActivistRERedmile Group, LLC9.9%May 14, 2026

ActivistADAdage Capital Management, L.P.8.6%May 13, 2026

ActivistPIPanacea Innovation Limited16.1%May 11, 2026

Activist

Point72 Asset Management, L.P.6.2%May 8, 2026

InsiderPLPanacea Innovation LtdSell $3.2MMay 7, 2026

ActivistECEcoR1 Capital, LLC17.4%May 7, 2026

InsiderNANguyen AnhCoSell $1KMar 2, 2026

InsiderNANguyen AnhCoSell $294.64Mar 2, 2026

InsiderNANguyen AnhCoSell $7KMar 2, 2026

View all insider trades View all activist filings

13F: Mar 31, 2026Insider & Congress: Updated regularly

Fund	Action	Shares	Value	Weight	Est. P&L	Conviction
AGADAGE CAPITAL PARTNERS GP, L.L.C.	New	700,000	$3.3M	0.0%	+80.07%	37
MACKENZIE FINANCIAL CORP	Increased	313,620(+434.6%)	$1.5M	0.0%	+47.80%	41
VAVANGUARD CAPITAL MANAGEMENT LLC	New	217,862	$1M	0.0%	+80.07%	38
Point72 Asset Management, L.P.	Increased	194,264(+961.8%)	$918,869	0.0%	+48.02%	40
BlackRock, Inc.	Increased	79,022(+17.8%)	$373,773	0.0%	-14.79%	19
GEODE CAPITAL MANAGEMENT, LLC	Increased	66,146(+6.0%)	$313,045	0.0%	-96.47%	17
UBS Group AG	Increased	50,070(+3484.1%)	$236,831	0.0%	+75.58%	25
MILLENNIUM MANAGEMENT LLC	New	47,689	$225,569	0.0%	+80.07%	32
JANE STREET GROUP, LLC	Increased	33,870(+142.1%)	$160,206	0.0%	+9.84%	25
VFVANGUARD FIDUCIARY TRUST CO	New	33,621	$159,027	0.0%	+80.07%	34
STATE STREET CORP	Unchanged	26,453	$125,123	0.0%	-16.73%	0
FMR LLC	Decreased	16,238(-5.3%)	$76,806	0.0%	-26.51%	0
NORTHERN TRUST CORP	Unchanged	12,340	$58,368	0.0%	-29.11%	0
MORGAN STANLEY	Decreased	9,169(-42.7%)	$43,370	0.0%	-20.01%	0
ROYAL BANK OF CANADA	Increased	4,319(+408.1%)	$20,000	0.0%	+67.38%	21
VGVanguard Global Advisers, LLC	New	1,456	$6,887	0.0%	+80.07%	25
JONES FINANCIAL COMPANIES LLLP	Unchanged	703	$3,227	0.0%	+15.11%	0
WELLS FARGO & COMPANY/MN	Unchanged	251	$1,187	0.0%	-33.98%	0
JPMORGAN CHASE & CO	Unchanged	216	$933	0.0%	-26.51%	0
RHUMBLINE ADVISERS	Unchanged	175	$827	0.0%	-97.99%	0