Jane Street’s REX Bitcoin Corporate Treasury Convertible Bond ETF BMAX Stock Holding History

Jane Street’s Portfolio BMAX Stock Details BMAX Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$893K	Buy	39,021 +5,621	+17%	+$132K	﹤0.01%	6772
2025 Q4	$770K	Buy	33,400 +15,101	+83%	+$384K	﹤0.01%	6715
2025 Q3	$520K	Sell	18,299 -22,985	-56%	-$670K	﹤0.01%	7784
2025 Q2	$1.23M	Sell	41,284 -689,524	-94%	-$19.7M	﹤0.01%	5244
2025 Q1	$18.5M	Buy	+730,808	New	+$19.3M	﹤0.01%	1374

Other funds holding BMAX

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

SBI Securities Tokyo, Japan $3.65B AUM 41.88% 1-Year Est. Return

Jane Street's BMAX Position: Q1 2026 in Review

Jane Street increased its REX Bitcoin Corporate Treasury Convertible Bond ETF (BMAX) stake by 17% in Q1 2026, buying an estimated $132K and bringing the position to 39,021 shares worth $893K. The position accounts for ﹤0.01% of the portfolio, ranked #6772.

Jane Street first reported a position in BMAX in Q1 2025 and has held it in 5 quarters since. The position peaked at $18.5M in Q1 2025. 3 funds tracked by Wall St. Rank hold BMAX as of Q1 2026.

Jane Street held 39,021 shares of REX Bitcoin Corporate Treasury Convertible Bond ETF worth $893K as of Q1 2026.
Jane Street bought 5,621 REX Bitcoin Corporate Treasury Convertible Bond ETF shares in Q1 2026, an estimated $132K.
REX Bitcoin Corporate Treasury Convertible Bond ETF made up ﹤0.01% of Jane Street's portfolio in Q1 2026, its #6772 holding.
Jane Street first reported a position in REX Bitcoin Corporate Treasury Convertible Bond ETF in Q1 2025 and has held it in 5 quarters since.
Jane Street's REX Bitcoin Corporate Treasury Convertible Bond ETF position peaked at $18.5M in Q1 2025.
3 funds tracked by Wall St. Rank held REX Bitcoin Corporate Treasury Convertible Bond ETF as of Q1 2026.

Based on Jane Street's 13F filing for Q1 2026, filed 12 May 2026.