Ken Griffin’s J-Star Holding Co YMAT Stock Holding History

Ken Griffin’s Portfolio YMAT Stock Details YMAT Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$6.23K	Buy	+4,432	New	+$9.56K	﹤0.01%	12802
2025 Q4	–	Sell	-13,706	Closed	-$82.2K	–	14668
2025 Q3	$82.2K	Buy	+13,706	New	+$200K	﹤0.01%	11956

Other funds holding YMAT

XTX Topco George Town, Cayman Islands $5.75B AUM 30.56% 1-Year Est. Return

Ken Griffin's YMAT Position: Q1 2026 in Review

Ken Griffin opened a new position in J-Star Holding Co (YMAT) in Q1 2026: 4,432 shares worth $6.23K. The stake represents ﹤0.01% of the portfolio and ranks #12802 among its holdings. This is a return to the name: Ken Griffin previously reported a position in YMAT as recently as Q3 2025.

Ken Griffin first reported a position in YMAT in Q3 2025 and has held it in 2 quarters since. The position peaked at $82.2K in Q3 2025. 2 funds tracked by Wall St. Rank hold YMAT as of Q1 2026.

Ken Griffin held 4,432 shares of J-Star Holding Co worth $6.23K as of Q1 2026.
J-Star Holding Co was a new Ken Griffin position in Q1 2026.
J-Star Holding Co made up ﹤0.01% of Ken Griffin's portfolio in Q1 2026, its #12802 holding.
Ken Griffin first reported a position in J-Star Holding Co in Q3 2025 and has held it in 2 quarters since.
Ken Griffin's J-Star Holding Co position peaked at $82.2K in Q3 2025.
2 funds tracked by Wall St. Rank held J-Star Holding Co as of Q1 2026.

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