Connor, Clark & Lunn Investment Management (CC&L)’s Atara Biotherapeutics ATRA Stock Holding History

Connor, Clark & Lunn Investment Management (CC&L)’s Portfolio ATRA Stock Details ATRA Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	–	Sell	-10,446	Closed	-$189K	–	1551
2025 Q4	$189K	Buy	+10,446	New	+$156K	﹤0.01%	1455
2022 Q4	–	Sell	-1,572	Closed	-$149K	–	1199
2022 Q3	$149K	Sell	1,572 -2,624	-63%	-$295K	﹤0.01%	1021
2022 Q2	$817K	Buy	4,196 +2,362	+129%	+$386K	0.01%	665
2022 Q1	$426K	Buy	1,834 +1,095	+148%	+$349K	﹤0.01%	811
2021 Q4	$291K	Buy	739 +100	+16%	+$42.1K	﹤0.01%	898
2021 Q3	$286K	Buy	+639	New	+$229K	﹤0.01%	883
2020 Q2	–	Sell	-521	Closed	-$111K	–	1010
2020 Q1	$111K	Buy	+521	New	+$165K	﹤0.01%	924

Other funds holding ATRA

Adage Capital Partners Boston, Massachusetts $64.8B AUM 42.7% 1-Year Est. Return

Redmile Group San Francisco, California $1.51B AUM 164.17% 1-Year Est. Return

Mackenzie Financial Toronto Ontario, Ontario, Canada $83.3B AUM 31.19% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

Point72 Asset Management Stamford, Connecticut $78.1B AUM 55.25% 1-Year Est. Return

Acadian Asset Management Boston, Massachusetts $70.5B AUM 36% 1-Year Est. Return

EcoR1 Capital San Francisco, California $2.36B AUM 204.53% 1-Year Est. Return

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

UBS Group Zurich, Switzerland $666B AUM 30.12% 1-Year Est. Return

Connor, Clark & Lunn Investment Management (CC&L)'s ATRA Position: Q1 2026 in Review

Connor, Clark & Lunn Investment Management (CC&L) sold out of Atara Biotherapeutics (ATRA) in Q1 2026, closing a stake of 10,446 shares — an estimated $189K sold.

Connor, Clark & Lunn Investment Management (CC&L) first reported a position in ATRA in Q1 2020 and held it in 7 quarters. The position peaked at $817K in Q2 2022. 33 funds tracked by Wall St. Rank hold ATRA as of Q1 2026.

Connor, Clark & Lunn Investment Management (CC&L) reported no remaining Atara Biotherapeutics position as of Q1 2026 after selling out during the quarter.
Connor, Clark & Lunn Investment Management (CC&L) sold 10,446 Atara Biotherapeutics shares in Q1 2026, an estimated $189K.
Connor, Clark & Lunn Investment Management (CC&L) first reported a position in Atara Biotherapeutics in Q1 2020 and held it in 7 quarters.
Connor, Clark & Lunn Investment Management (CC&L)'s Atara Biotherapeutics position peaked at $817K in Q2 2022.
33 funds tracked by Wall St. Rank held Atara Biotherapeutics as of Q1 2026.

Based on Connor, Clark & Lunn Investment Management (CC&L)'s 13F filing for Q1 2026, filed 11 May 2026.