Ken Griffin’s ATS Corp ATS Stock Holding History

Ken Griffin’s Portfolio ATS Stock Details ATS Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$2.29M	Sell	81,239 -67,601	-45%	-$2.03M	﹤0.01%	5801
2025 Q4	$4.1M	Buy	148,840 +79,020	+113%	+$2.11M	﹤0.01%	4601
2025 Q3	$1.83M	Buy	69,820 +43,728	+168%	+$1.26M	﹤0.01%	6253
2025 Q2	$832K	Buy	+26,092	New	+$715K	﹤0.01%	7494
2025 Q1	–	Sell	-4,919	Closed	-$137K	–	14438
2024 Q4	$150K	Sell	4,919 -118,661	-96%	-$3.6M	﹤0.01%	10884
2024 Q3	$3.59M	Buy	123,580 +92,433	+297%	+$2.67M	﹤0.01%	4483
2024 Q2	$1.01M	Sell	31,147 -27,556	-47%	-$889K	﹤0.01%	6561
2024 Q1	$1.98M	Buy	58,703 +9,391	+19%	+$373K	﹤0.01%	5540
2023 Q4	$2.12M	Buy	+49,312	New	+$1.91M	﹤0.01%	5255
2023 Q3	–	Sell	-605,132	Closed	-$27.9M	–	14255
2023 Q2	$27.9M	Buy	+605,132	New	+$27.2M	0.01%	1551

Other funds holding ATS

MCM

Mason Capital Management New York $613M AUM 21.43% 1-Year Est. Return

Royal Bank of Canada Toronto, Ontario, Canada $570B AUM 27.57% 1-Year Est. Return

EIG

EdgePoint Investment Group Toronto, Ontario, Canada $12.5B AUM 31.7% 1-Year Est. Return

BGC

Beutel, Goodman & Co Toronto, Ontario, Canada $13.6B AUM 17.82% 1-Year Est. Return

TCAM

Turtle Creek Asset Management Toronto, Ontario, Canada $2.67B AUM 0.64% 1-Year Est. Return

Bank of Montreal Toronto, Ontario, Canada $304B AUM 35.64% 1-Year Est. Return

FFH

Fairfax Financial Holdings Toronto, Ontario, Canada $1.94B AUM 27.76% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

Janus Henderson Group London, United Kingdom $209B AUM 37.72% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

Ken Griffin's ATS Position: Q1 2026 in Review

Ken Griffin reduced its ATS Corp (ATS) stake by 45% in Q1 2026, selling an estimated $2.03M and leaving 81,239 shares worth $2.29M. The position accounts for ﹤0.01% of the portfolio, ranked #5801.

Ken Griffin first reported a position in ATS in Q2 2023 and has held it in 10 quarters since. The position peaked at $27.9M in Q2 2023. 130 funds tracked by Wall St. Rank hold ATS as of Q1 2026.

Ken Griffin held 81,239 shares of ATS Corp worth $2.29M as of Q1 2026.
Ken Griffin sold 67,601 ATS Corp shares in Q1 2026, an estimated $2.03M.
ATS Corp made up ﹤0.01% of Ken Griffin's portfolio in Q1 2026, its #5801 holding.
Ken Griffin first reported a position in ATS Corp in Q2 2023 and has held it in 10 quarters since.
Ken Griffin's ATS Corp position peaked at $27.9M in Q2 2023.
130 funds tracked by Wall St. Rank held ATS Corp as of Q1 2026.

Based on Citadel Advisors's 13F filing for Q1 2026, filed 15 May 2026.