Quartzsea Acquisition Corp
QSEAU- Exchange
- Nasdaq
- Industry
- Blank Checks
- SEC CIK
- 0002047455
No open-market purchases or sales by Quartzsea Acquisition Corp insiders were filed in the last 90 days; 2 institutions reported holding it in 13F filings for Q2 2026, worth $321.2K in total; no superinvestor holds it.
Holders of 5% or more of QSEAU
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Quartzsea Acquisition Corp, largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| Mizuho Financial Group Inc | 13G | 5.60%641.8K shares | −3.40 ppfrom 9.00% | May 13, 20252 filings | Nov 13, 2025 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
7 Schedule 13D and 13G filings on Quartzsea Acquisition Corp, newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Nov 13, 20256:09 AM ET | Mizuho Financial Group Inc | 13G | 5.60%641.8K shares | −3.40 ppfrom 9.00% | Sep 30, 2025 | SEC |
| Aug 14, 20258:30 AM ET | Harraden Circle Investments, LLCand 6 others | 13G/A | 0.00%0 shares | −8.71 ppfrom 8.71%Below 5% | Jun 30, 2025 | SEC |
| Aug 12, 20252:12 PM ET | TD Securities (USA) LLCand 3 others | 13G/A | 2.50%280.1K shares | −4.90 ppfrom 7.40%Below 5% | Jun 30, 2025 | SEC |
| May 13, 202510:02 AM ET | TD Securities (USA) LLCand 3 others | 13G | 7.40%612.5K shares | New | Mar 31, 2025 | SEC |
| May 13, 20257:03 AM ET | Mizuho Financial Group Inc | 13G | 9.00%856.0K shares | New | Mar 31, 2025 | SEC |
| Mar 25, 202511:24 AM ET | Feis Equities LLCand 1 other | 13G | 9.84%814.8K shares | New | Mar 18, 2025 | SEC |
| Mar 21, 20256:30 PM ET | Harraden Circle Investments, LLCand 6 others | 13G | 8.71%993.8K shares | New | Mar 18, 2025 | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Quartzsea Acquisition Corp shares.
No Form 144 notices for Quartzsea Acquisition Corp are on file.