Latest Period
Q2 2026
Security Snapshot
Quantumsphere Acquisition Corp - Class A ordinary shares, par value $0.0001 per share (QUMS) Institutional Ownership
CUSIP: G7387B106
13F Institutional Holders and Ownership History from Q3 2025 to Q2 2026
Institutions Reporting
27
Shares (Excl. Options)
7,858,263
Price
$10.22
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- Security type / class
- Equity / Class A ordinary shares, par value $0.0001 per share
- Symbol
- QUMS on Nasdaq
- All holders as of 30 Jun 2026
- Q2 2026
- Total 13F shares
- 7,858,263
- Total 13F value
- $80,303,803
- Portfolio coverage rank
- 0%
- Share change
- +302,685
- Value change
- +$3,134,812
- Number of holders
- 27
- Shares outstanding
- 11,446,779
- SEC-reported price per share
- $10.29
Latest holder snapshot
5 signals
Issuer context
Names, identifiers, and filing context for this profile.
2 identity fields
13F Shares, Excluding Options vs Price
13F Value, Excluding Options
Total Investors
Key facts
- QUMS - Quantumsphere Acquisition Corp - Class A ordinary shares, par value $0.0001 per share is tracked under CUSIP G7387B106.
- 27 institutions reported positions in Q2 2026.
- 4 significant owners is listed from Schedule 13D/13G reporting.
Change
- Holder count moved from 29 to 27 between Q1 2026 and Q2 2026.
- SEC-reported value moved from $76,411,551 to $80,303,803.
Research use
- You can quickly see who holds this security, then open quarter and manager detail pages for full evidence.
- 13F and Schedule 13D/13G sections are kept together so you can cross-check institutional and beneficial ownership context.
Evidence
Source: SEC Form 13F
Open SEC evidence
Latest holder context comes from 27 institutions filings for Q2 2026.
Security key
G7387B106
Latest holder period
Q2 2026
13F holders
27
13D/G owners
4
CIK / CUSIP context first
Open Q2 2026 holders
QUMS full holder history
Quantumsphere Acquisition Corp SEC filings
Quantumsphere Acquisition Corp company facts
Quantumsphere Acquisition Corp insider transactions
Broader feeds
Recent Quarterly Holder Reports
Open recent reporting periods for CUSIP G7387B106:
13D/G owners
Significant owners
Large-stake holder rows connected to Schedule 13D/G evidence.
Rows
4
Security
QUMS
| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| Whiteowl Holdings LLC | 27% | 3,126,650 | Whiteowl Holdings LLC | 05 Aug 2025 | ||||
| BERKLEY W R CORP | 7.7% | $9,034,370 | 881,402 | W. R. Berkley Corporation | 30 Jun 2026 | |||
| MIZUHO FINANCIAL GROUP INC | 6.3% | $7,188,041 | 718,086 | Mizuho Financial Group, Inc. | 31 Dec 2025 | |||
| WOLVERINE ASSET MANAGEMENT LLC | 5% | 574,171 | WOLVERINE ASSET MANAGEMENT LLC | 31 Oct 2025 |
As of 30 Jun 2026, 27 institutional investors reported holding 7,858,263 shares of Quantumsphere Acquisition Corp - Class A ordinary shares, par value $0.0001 per share (QUMS). This represents 69% of the company’s total 11,446,779 outstanding shares.
13F concentration
Top 25 institutional shareholders
Largest 13F positions for this security by reported shares and value.
Top holder share
69%
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| BERKLEY W R CORP | 7.7% | 881,402 | +73% | 0.44% | $9,007,928 |
| MIZUHO SECURITIES USA LLC | 6.6% | 757,023 | +3.4% | 0.12% | $7,683,783 |
| WOLVERINE ASSET MANAGEMENT LLC | 5.3% | 602,984 | -0.17% | 0.08% | $6,162,496 |
| Karpus Management, Inc. | 4.1% | 469,875 | -4.9% | 0.14% | $4,802,123 |
| RIVERNORTH CAPITAL MANAGEMENT, LLC | 3.7% | 424,124 | -0.09% | 0.21% | $4,368,477 |
| D. E. Shaw & Co., Inc. | 3.6% | 409,860 | 0% | 0% | $4,188,769 |
| Shaolin Capital Management LLC | 3.5% | 405,761 | -15% | 0.39% | $4,146,877 |
| GLAZER CAPITAL, LLC | 3.5% | 400,089 | -5.4% | 0.1% | $4,089,000 |
| Linden Advisors LP | 3.5% | 400,000 | 0% | 0.02% | $4,088,000 |
| Polar Asset Management Partners Inc. | 3.5% | 400,000 | 0% | 0.08% | $4,088,000 |
| HIGHBRIDGE CAPITAL MANAGEMENT LLC | 3.3% | 377,607 | +212% | 0.13% | $3,870,472 |
| Westchester Capital Management, LLC | 3.1% | 350,000 | +40% | 0.18% | $3,576,999 |
| AQR Arbitrage LLC | 2.7% | 312,523 | +1.4% | 0.05% | $3,193,985 |
| RLH Capital LLC | 2.2% | 250,000 | +150% | 1.2% | $2,555,000 |
| Hudson Bay Capital Management LP | 2.1% | 235,000 | 0% | 0.01% | $2,401,700 |
| Cable Car Capital, LP | 1.5% | 174,801 | 0% | 0.04% | $1,786,466 |
| Clear Street Group Inc. | 1.4% | 164,793 | -5.8% | 0.01% | $1,684,184 |
| Radcliffe Capital Management, L.P. | 1.3% | 150,000 | 0% | 0.12% | $1,533,000 |
| HEIGHTS CAPITAL MANAGEMENT, INC | 1.3% | 150,000 | 0% | 0.35% | $1,533,000 |
| BNP PARIBAS FINANCIAL MARKETS | 1% | 115,048 | 0% | 0% | $1,175,791 |
| Crossingbridge Advisors, LLC | 0.94% | 107,825 | 0% | 0.19% | $1,101,972 |
| TORONTO DOMINION BANK | 0.87% | 100,000 | -62% | 0% | $1,022,000 |
| Quarry LP | 0.66% | 75,000 | 0.12% | $766,500 | |
| Periscope Capital Inc. | 0.66% | 75,000 | -25% | 0.12% | $766,500 |
| Schonfeld Strategic Advisors LLC | 0.48% | 55,000 | 0% | 0% | $562,100 |
Quarter history
Institutional holders across reporting periods
Holder count, reported shares/value, and median price by quarter.
Periods
4
Latest
Q2 2026
Rows shown
1-4 of 4