Jane Street’s T-Rex 2X Inverse MSTR Daily Target ETF MSTZ Stock Holding History

Jane Street’s Portfolio MSTZ Stock Details MSTZ Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$741K	Buy	59,400 +3,000	+5%	+$40.1K	﹤0.01%	7148
2025 Q4	$967K	Sell	56,400 -149,900	-73%	-$1.52M	﹤0.01%	6191
2025 Q3	$1.09M	Buy	206,300 +45,200	+28%	+$203K	﹤0.01%	6148
2025 Q2	$673K	Sell	161,100 -472,550	-75%	-$2.96M	﹤0.01%	6377
2025 Q1	$8.89M	Buy	633,650 +619,615	+4,415%	+$10.9M	﹤0.01%	2148
2024 Q4	$394K	Buy	+14,035	New	+$1.2M	﹤0.01%	7255

Other funds holding MSTZ

Susquehanna International Group Bala Cynwyd, Pennsylvania $893B AUM 36.07% 1-Year Est. Return

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

Elequin Capital New York $1.19B AUM 16.08% 1-Year Est. Return

StoneX Group New York $1.86B AUM 21.3% 1-Year Est. Return

FTUS

Flow Traders U.S. New York $3.16B AUM 19.52% 1-Year Est. Return

TSS

Two Sigma Securities New York $861M AUM 21.33% 1-Year Est. Return

GTS Securities New York $2.83B AUM 21.76% 1-Year Est. Return

IMC Chicago Chicago, Illinois $278B AUM 44.93% 1-Year Est. Return

Jump Financial Chicago, Illinois $7.5B AUM 33.9% 1-Year Est. Return

Optiver Holding Amsterdam, Netherlands $289B AUM 33.63% 1-Year Est. Return

Jane Street's MSTZ Position: Q1 2026 in Review

Jane Street reduced its T-Rex 2X Inverse MSTR Daily Target ETF (MSTZ) stake by 79% in Q1 2026, selling an estimated $990K and leaving 19,533 shares worth $244K. The position accounts for ﹤0.01% of the portfolio, ranked #9685.

Jane Street first reported a position in MSTZ in Q3 2024 and has held it in 6 quarters since. The position peaked at $7.1M in Q4 2024. 16 funds tracked by Wall St. Rank hold MSTZ as of Q1 2026.

Jane Street held 19,533 shares of T-Rex 2X Inverse MSTR Daily Target ETF worth $244K as of Q1 2026.
Jane Street sold 74,095 T-Rex 2X Inverse MSTR Daily Target ETF shares in Q1 2026, an estimated $990K.
T-Rex 2X Inverse MSTR Daily Target ETF made up ﹤0.01% of Jane Street's portfolio in Q1 2026, its #9685 holding.
Jane Street first reported a position in T-Rex 2X Inverse MSTR Daily Target ETF in Q3 2024 and has held it in 6 quarters since.
Jane Street's T-Rex 2X Inverse MSTR Daily Target ETF position peaked at $7.1M in Q4 2024.
16 funds tracked by Wall St. Rank held T-Rex 2X Inverse MSTR Daily Target ETF as of Q1 2026.

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