Westchester Capital Management (New York)’s Quantumsphere Acquisition Corp Units QUMSU Stock Holding History

Westchester Capital Management (New York)’s Portfolio QUMSU Stock Details QUMSU Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	–	Sell	-100,000	Closed	-$1.01M	–	368
2026 Q1	$1.01M	Hold	100,000	–	–	0.05%	200
2025 Q4	$1.02M	Hold	100,000	–	–	0.04%	186
2025 Q3	$1.01M	Buy	+100,000	New	+$1M	0.05%	169

Other funds holding QUMSU

GCIA

Gabelli & Co Investment Advisers Rye, New York $688M AUM 63.4% 1-Year Est. Return

Gabelli Funds Rye, New York $15.7B AUM 36.4% 1-Year Est. Return

HRT Financial New York $54.8B AUM 81.03% 1-Year Est. Return

Clear Street New York $39.5B AUM 124.03% 1-Year Est. Return

JP Morgan Chase New York $1.81T AUM 41.13% 1-Year Est. Return

UBS Group Zurich, Switzerland $786B AUM 40.34% 1-Year Est. Return

Westchester Capital Management (New York)'s QUMSU Position: Q2 2026 in Review

Westchester Capital Management (New York) sold out of Quantumsphere Acquisition Corp Units (QUMSU) in Q2 2026, closing a stake of 100,000 shares — an estimated $1.01M sold.

Westchester Capital Management (New York) first reported a position in QUMSU in Q3 2025 and held it in 3 quarters. The position peaked at $1.02M in Q4 2025. 6 funds tracked by Wall St. Rank hold QUMSU as of Q2 2026.

Westchester Capital Management (New York) reported no remaining Quantumsphere Acquisition Corp Units position as of Q2 2026 after selling out during the quarter.
Westchester Capital Management (New York) sold 100,000 Quantumsphere Acquisition Corp Units shares in Q2 2026, an estimated $1.01M.
Westchester Capital Management (New York) first reported a position in Quantumsphere Acquisition Corp Units in Q3 2025 and held it in 3 quarters.
Westchester Capital Management (New York)'s Quantumsphere Acquisition Corp Units position peaked at $1.02M in Q4 2025.
6 funds tracked by Wall St. Rank held Quantumsphere Acquisition Corp Units as of Q2 2026.

Based on Westchester Capital Management (New York)'s 13F filing for Q2 2026, filed 14 Aug 2026.