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.
Insider Transactions Reported by 5 Insiders of Quantumsphere Acquisition Corp
- Symbol
- QUMS, QUMSR, QUMSU on Nasdaq
- Location
- New York, NY
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.
Source Evidence
Filed on Form 4
See Original Filing
Issuer insider activity is sourced from SEC Forms 3, 4, and 5.
Insider trading overview
Last 12 monthsInsider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 14 May 2025.
Buys
$0
Shares: 0
Insiders: 0
Sells
$0
Shares: 0
Insiders: 0
Net
$0
Shares: 0
Insiders: 0
| Window (months) | Buy shares | Sell shares | Buy $ | Sell $ | Net $ |
|---|---|---|---|---|---|
| 0-3 | 0 | 0 | $0 | $0 | $0 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Quantumsphere Acquisition Corp executives and other stock owners filed with the SEC include:
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | 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 | |
| MIZUHO SECURITIES USA LLC |
13F
|
Company |
6.3%
|
718,086
|
$7,128,939 | — | 31 Dec 2025 | |
| WOLVERINE ASSET MANAGEMENT LLC |
13F
13D/G
|
Company |
5%
from 13D/G
|
725,222
mixed-class rows
|
$5,789,487 | — | 31 Dec 2025 | |
| Karpus Management, Inc. |
13F
|
Company |
4.3%
|
494,350
|
$4,948,444 | — | 31 Dec 2025 | |
| Shaolin Capital Management LLC |
13F
|
Company |
—
mixed-class rows
|
940,000
mixed-class rows
|
$4,901,446 | — | 31 Dec 2025 | |
| Clear Street Group Inc. |
13F
|
Company |
—
mixed-class rows
|
668,880
mixed-class rows
|
$4,451,370 | — | 31 Dec 2025 | |
| GLAZER CAPITAL, LLC |
13F
|
Company |
—
mixed-class rows
|
844,689
mixed-class rows
|
$4,334,000 | — | 31 Dec 2025 | |
| RIVERNORTH CAPITAL MANAGEMENT, LLC |
13F
|
Company |
—
class O/S missing
|
424,512
|
$4,321,532 | — | 31 Dec 2025 | |
| D. E. Shaw & Co., Inc. |
13F
|
Company |
—
mixed-class rows
|
534,860
mixed-class rows
|
$4,128,962 | — | 31 Dec 2025 | |
| LINDEN ADVISORS LP |
13F
|
Company |
—
mixed-class rows
|
800,000
mixed-class rows
|
$4,092,000 | — | 31 Dec 2025 | |
| Polar Asset Management Partners Inc. |
13F
|
Company |
—
class O/S missing
|
400,000
|
$4,072,000 | — | 31 Dec 2025 | |
| Westchester Capital Management, LLC |
13F
|
Company |
—
mixed-class rows
|
350,000
mixed-class rows
|
$3,520,501 | — | 31 Dec 2025 | |
| AQR Arbitrage LLC |
13F
|
Company |
—
mixed-class rows
|
645,320
mixed-class rows
|
$3,294,391 | — | 31 Dec 2025 | |
| HGC Investment Management Inc. |
13F
|
Company |
—
mixed-class rows
|
600,000
mixed-class rows
|
$3,066,030 | — | 31 Dec 2025 | |
| BERKLEY W R CORP |
13F
|
Company |
—
mixed-class rows
|
338,690
mixed-class rows
|
$3,046,213 | — | 31 Dec 2025 | |
| Hudson Bay Capital Management LP |
13F
|
Company |
—
mixed-class rows
|
385,000
mixed-class rows
|
$2,383,865 | — | 31 Dec 2025 | |
| TWO SIGMA INVESTMENTS, LP |
13F
|
Company |
1.9%
|
217,479
|
$2,176,965 | — | 31 Dec 2025 | |
| TORONTO DOMINION BANK |
13F
|
Company |
—
mixed-class rows
|
870,915
mixed-class rows
|
$1,905,517 | — | 31 Dec 2025 | |
| Cable Car Capital, LP |
13F
|
Company |
—
mixed-class rows
|
349,602
mixed-class rows
|
$1,786,484 | — | 31 Dec 2025 | |
| Radcliffe Capital Management, L.P. |
13F
|
Company |
—
mixed-class rows
|
300,000
mixed-class rows
|
$1,534,500 | — | 31 Dec 2025 | |
| HEIGHTS CAPITAL MANAGEMENT, INC |
13F
|
Company |
—
mixed-class rows
|
299,900
mixed-class rows
|
$1,532,994 | — | 31 Dec 2025 | |
| PERISCOPE CAPITAL INC. |
13F
|
Company |
—
mixed-class rows
|
250,000
mixed-class rows
|
$1,277,513 | — | 31 Dec 2025 | |
| BNP PARIBAS FINANCIAL MARKETS |
13F
|
Company |
—
mixed-class rows
|
204,680
mixed-class rows
|
$1,045,914 | — | 31 Dec 2025 | |
| GABELLI & Co INVESTMENT ADVISERS, INC. |
13F
|
Company |
—
class O/S missing
|
67,700
|
$689,186 | — | 31 Dec 2025 | |
| GABELLI FUNDS LLC |
13F
|
Company |
—
class O/S missing
|
57,300
|
$583,314 | — | 31 Dec 2025 | |
| Schonfeld Strategic Advisors LLC |
13F
|
Company |
—
mixed-class rows
|
109,599
mixed-class rows
|
$562,021 | — | 31 Dec 2025 | |
| Warberg Asset Management LLC |
13F
|
Company |
0.36%
|
41,421
|
$414,624 | — | 31 Dec 2025 | |
| HRT FINANCIAL LP |
13F
|
Company |
—
class O/S missing
|
31,089
|
$316,000 | — | 31 Dec 2025 | |
| Virtu Financial LLC |
13F
|
Company |
0.22%
|
24,783
|
$248,000 | — | 31 Dec 2025 | |
| Harraden Circle Investments, LLC |
13F
|
Company |
—
class O/S missing
|
993,926
|
$208,824 | — | 31 Dec 2025 | |
| Logan Stone Capital, LLC |
13F
|
Company |
0.13%
|
14,500
|
$145,145 | — | 31 Dec 2025 | |
| HIGHBRIDGE CAPITAL MANAGEMENT LLC |
13F
|
Company |
—
class O/S missing
|
684,037
|
$143,716 | — | 31 Dec 2025 | |
| JPMORGAN CHASE & CO |
13F
|
Company |
—
class O/S missing
|
10,000
|
$101,800 | — | 31 Dec 2025 | |
| BOOTHBAY FUND MANAGEMENT, LLC |
13F
|
Company |
—
class O/S missing
|
100,000
|
$21,010 | — | 31 Dec 2025 | |
| UBS Group AG |
13F
|
Company |
—
mixed-class rows
|
16,563
mixed-class rows
|
$8,055 | — | 31 Dec 2025 | |
| METEORA CAPITAL, LLC |
13F
|
Company |
—
class O/S missing
|
36,121
|
$7,589 | — | 31 Dec 2025 | |
| MORGAN STANLEY |
13F
|
Company |
0%
|
30
|
$300 | — | 31 Dec 2025 | |
| BANK OF AMERICA CORP /DE/ |
13F
|
Company |
—
class O/S missing
|
100
|
$21 | — | 31 Dec 2025 | |
| Ping Zhang |
3/4/5
|
Chairman, CEO, and CFO, Director |
—
class O/S missing
|
3,126,650
|
— | — | 05 Aug 2025 | |
| Whiteowl Holdings LLC |
3/4/5
13D/G
|
10%+ Owner |
27%
from 13D/G
|
3,126,650
|
— | — | 05 Aug 2025 |
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.