Insider Transactions Reported by 5 Insiders of Quantumsphere Acquisition Corp

Symbol: QUMS, QUMSR, QUMSU on Nasdaq
Location: New York, NY

Quick Takeaways

QUMS - Quantumsphere Acquisition Corp has 5 insiders with reported activity on this page.
No net insider buy/sell flow is currently reported for the last year.
Recent transaction rows are available for direct filing-level review.

What Changed

No meaningful buy/sell imbalance is currently visible in the one-year window.
Activity will update as new Forms 3/4/5 are filed.

Why This Matters

This page gives a plain-language issuer insider context before you inspect transaction-level evidence.
Use the filing links below to verify timestamps, codes, and ownership impacts directly from SEC forms.

Official SEC Source

Filed on Form 4

Issuer insider activity is sourced from SEC Forms 3, 4, and 5.

See Original Filing

Insider trading overview

Last 12 months

Insider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 13 Apr 2025.

Buys

Shares: 0

Insiders: 0

Sells

Shares: 0

Insiders: 0

Net

Shares: 0

Insiders: 0

Window (months)	Buy $	Sell $	Net $
0-3	$0	$0	$0
3-6	$0	$0	$0
6-9	$0	$0	$0
9-12	$0	$0	$0

Quantumsphere Acquisition Corp executives and other stock owners filed with the SEC include:

Name	Relationship	Valuation	Report Date
Wei Zhang	Director	Mixed	05 Aug 2025
Whiteowl Holdings LLC	10%+ Owner	Mixed	05 Aug 2025
Qi Gong	Director	Mixed	05 Aug 2025
Ping Zhang	Chairman, CEO, and CFO, Director	Mixed	05 Aug 2025
Daniel M. McCabe	Director	Mixed	05 Aug 2025

Top shareholders of Quantumsphere Acquisition Corp (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.

Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

Holder	Source	Role / Reporting	Ownership %	Shares	Holdings Value	12M Net Δ	As of	Details
MIZUHO FINANCIAL GROUP INC	13D/G	—	6.3%	718,086	$7,188,041	$0	31 Dec 2025	13D/G
MIZUHO SECURITIES USA LLC	13F	Company	6.3%	718,086	$7,128,939	—	31 Dec 2025	13F
WOLVERINE ASSET MANAGEMENT LLC	13F 13D/G	Company	5% from 13D/G	725,222 mixed-class rows	$5,789,487	—	31 Dec 2025	13F 13D/G
Karpus Management, Inc.	13F	Company	4.3%	494,350	$4,948,444	—	31 Dec 2025	13F
Shaolin Capital Management LLC	13F	Company	— mixed-class rows	940,000 mixed-class rows	$4,901,446	—	31 Dec 2025	13F
Clear Street Group Inc.	13F	Company	— mixed-class rows	668,880 mixed-class rows	$4,451,370	—	31 Dec 2025	13F
GLAZER CAPITAL, LLC	13F	Company	— mixed-class rows	844,689 mixed-class rows	$4,334,000	—	31 Dec 2025	13F
RIVERNORTH CAPITAL MANAGEMENT, LLC	13F	Company	— class O/S missing	424,512	$4,321,532	—	31 Dec 2025	13F
D. E. Shaw & Co., Inc.	13F	Company	— mixed-class rows	534,860 mixed-class rows	$4,128,962	—	31 Dec 2025	13F
LINDEN ADVISORS LP	13F	Company	— mixed-class rows	800,000 mixed-class rows	$4,092,000	—	31 Dec 2025	13F
Polar Asset Management Partners Inc.	13F	Company	— class O/S missing	400,000	$4,072,000	—	31 Dec 2025	13F
Westchester Capital Management, LLC	13F	Company	— mixed-class rows	350,000 mixed-class rows	$3,520,501	—	31 Dec 2025	13F
AQR Arbitrage LLC	13F	Company	— mixed-class rows	645,320 mixed-class rows	$3,294,391	—	31 Dec 2025	13F
HGC Investment Management Inc.	13F	Company	— mixed-class rows	600,000 mixed-class rows	$3,066,030	—	31 Dec 2025	13F
BERKLEY W R CORP	13F	Company	— mixed-class rows	338,690 mixed-class rows	$3,046,213	—	31 Dec 2025	13F
Hudson Bay Capital Management LP	13F	Company	— mixed-class rows	385,000 mixed-class rows	$2,383,865	—	31 Dec 2025	13F
TWO SIGMA INVESTMENTS, LP	13F	Company	1.9%	217,479	$2,176,965	—	31 Dec 2025	13F
TORONTO DOMINION BANK	13F	Company	— mixed-class rows	870,915 mixed-class rows	$1,905,517	—	31 Dec 2025	13F
Cable Car Capital, LP	13F	Company	— mixed-class rows	349,602 mixed-class rows	$1,786,484	—	31 Dec 2025	13F
Radcliffe Capital Management, L.P.	13F	Company	— mixed-class rows	300,000 mixed-class rows	$1,534,500	—	31 Dec 2025	13F
HEIGHTS CAPITAL MANAGEMENT, INC	13F	Company	— mixed-class rows	299,900 mixed-class rows	$1,532,994	—	31 Dec 2025	13F
PERISCOPE CAPITAL INC.	13F	Company	— mixed-class rows	250,000 mixed-class rows	$1,277,513	—	31 Dec 2025	13F
BNP PARIBAS FINANCIAL MARKETS	13F	Company	— mixed-class rows	204,680 mixed-class rows	$1,045,914	—	31 Dec 2025	13F
GABELLI & Co INVESTMENT ADVISERS, INC.	13F	Company	— class O/S missing	67,700	$689,186	—	31 Dec 2025	13F
GABELLI FUNDS LLC	13F	Company	— class O/S missing	57,300	$583,314	—	31 Dec 2025	13F
Schonfeld Strategic Advisors LLC	13F	Company	— mixed-class rows	109,599 mixed-class rows	$562,021	—	31 Dec 2025	13F
Warberg Asset Management LLC	13F	Company	0.36%	41,421	$414,624	—	31 Dec 2025	13F
HRT FINANCIAL LP	13F	Company	— class O/S missing	31,089	$316,000	—	31 Dec 2025	13F
Virtu Financial LLC	13F	Company	0.22%	24,783	$248,000	—	31 Dec 2025	13F
Harraden Circle Investments, LLC	13F	Company	— class O/S missing	993,926	$208,824	—	31 Dec 2025	13F
Logan Stone Capital, LLC	13F	Company	0.13%	14,500	$145,145	—	31 Dec 2025	13F
HIGHBRIDGE CAPITAL MANAGEMENT LLC	13F	Company	— class O/S missing	684,037	$143,716	—	31 Dec 2025	13F
JPMORGAN CHASE & CO	13F	Company	— class O/S missing	10,000	$101,800	—	31 Dec 2025	13F
BOOTHBAY FUND MANAGEMENT, LLC	13F	Company	— class O/S missing	100,000	$21,010	—	31 Dec 2025	13F
UBS Group AG	13F	Company	— mixed-class rows	16,563 mixed-class rows	$8,055	—	31 Dec 2025	13F
METEORA CAPITAL, LLC	13F	Company	— class O/S missing	36,121	$7,589	—	31 Dec 2025	13F
MORGAN STANLEY	13F	Company	0%	30	$300	—	31 Dec 2025	13F
BANK OF AMERICA CORP /DE/	13F	Company	— class O/S missing	100	$21	—	31 Dec 2025	13F
Ping Zhang	3/4/5	Chairman, CEO, and CFO, Director	— class O/S missing	3,126,650	—	—	05 Aug 2025	3/4/5
Whiteowl Holdings LLC	3/4/5 13D/G	10%+ Owner	27% from 13D/G	3,126,650	—	—	05 Aug 2025	3/4/5 13D/G

Recent Insider Transactions by Companies or Individuals for Quantumsphere Acquisition Corp

Showing up to 300 most recent insider transactions from the last 12 months.

Insider	Symbol	Class	Transaction	%	Value $	* Price $	Shares	Shares Owned	Date	Ownership
Whiteowl Holdings LLC	QUMS	Ordinary Shares, par value $0.0001 per share					0	3,126,650	05 Aug 2025	Direct
Ping Zhang	QUMS	Ordinary Shares, par value $0.0001 per share					0	3,126,650	05 Aug 2025	See footnote

* An asterisk sign (*) next to the price indicates that the price is likely invalid.