QUMSU QUANTUMSPHERE ACQUISITION CO
FollowUNIT 07/30/2030 (unit), issuer CIK 2070900
8 managers (9 13F filers) reported a position in QUMSU shares at 2025-12-31, 1,105,926 shares in all. 1 filer opened a position and 21 filers sold out during the quarter.
- Managers
- 8
- 13F filers
- 9
- New
- 1
- Added
- 1
- Reduced
- 2
- Sold out
- 21
- Shares held by filers
- 1,105,926
Shares held by filers adds up every 13F filer's report, so a share reported by a parent and by its subsidiary counts twice (H9). Managers counts each filer group once.
13D and 13G filers
No 13D or 13G on this security in the data. Structured 13D/G data starts 2024-12-18.
Insider trades
No Form 4 transaction on this security in the data.
13F holders, Q4 2025
Filers in the available 13F reports with a share position at 2025-12-31, filer groups collapsed to one row (method), largest first. Options and principal amounts are left out. A group row states no % of portfolio, since each member reports its own portfolio: the members' percents are listed under it. A value about 1,000 times or 1/1,000 of the price other filers imply is shown as filed but neither ranks the row nor enters a sum.
| Holder | Shares | Value | % of portfolio | Change | Source |
|---|---|---|---|---|---|
| RIVERNORTH CAPITAL MANAGEMENT, LLC | 424,512 | $4.32M | 0.2% | -488 | 13F-HRTimeline |
| Polar Asset Management Partners Inc. | 400,000 | $4.07M | 0.08% | 0 | 13F-HRTimeline |
| GAMCO Investors (Gabelli)group of 2 filers holding | 125,000 | $1.27M | 0 | Timeline
| |
| Westchester Capital Management, LLCin group Westchester Capital Managemen… | 100,000 | $1.02M | 0.05% | 0 | 13F-HRTimelineGroup |
| HRT FINANCIAL LP | 31,089 | $316K | <0.01% | +1,104 | 13F-HRTimeline |
| Clear Street Group Inc.in group Clear Street Group Inc. | 14,866 | $151K | <0.01% | -203,191 | 13F-HRTimelineGroup |
| JPMORGAN CHASE & COin group JPMORGAN CHASE & CO | 10,000 | $102K | <0.01% | 0 | 13F-HRTimelineGroup |
| UBS Group AGin group UBS Group AG | 459 | $4.67K | <0.01% | new | 13F-HRTimelineGroup |