As of November 7, 2026, C3is Inc. is a publicly traded company (Nasdaq: CISS). Imperial Petroleum Inc. reports holding 80.5%, a majority of its shares. No bankruptcy or receivership appears in its SEC Form 8-K filings. Passive holders reporting on Schedule 13G include CVI Investments, Inc. (9.9%), Horne Timothy P (9.1%) (Schedule 13D/A, August 28, 2026).
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Is C3is Inc. a real, registered company?
- C3is Inc. files with the SEC under CIK 1951067 (its SEC filings).
- Its shares are listed under the ticker CISS on Nasdaq (SEC company record).
- Incorporated in 1T; business address in Athens, J3, as its SEC filings state.
- Court and bankruptcy records: see Before you sign or pay below.
Before you sign or pay
- Court and bankruptcy: No federal court case or bankruptcy filing found under C3is Inc. in our court records and SEC 8-K records (as of 2026-11-07).
- Ownership: 5%+ holders are reported on Schedule 13D or 13G; the latest names Horne Timothy P (filed 2026-09-03).
Who are C3is Inc.'s owners and officers?
C3is Inc.: business address in Athens, J3; industry Deep Sea Foreign Transportation of Freight (Schedule 13G/A, 2026-11-06).
| Report | Holder | Share |
|---|---|---|
| Schedule 13G/A, 2026-11-06 | Jane Street Group, LLC | 0.5% |
| Schedule 13G/A, 2026-10-05 | Alta Partners LLC | 3.1% |
| Schedule 13G/A, 2026-10-05 | Ascent Partners Fund LLC | 0% |
| Schedule 13G/A, 2026-10-02 | Towerview LLC | — |
| Schedule 13G, 2026-09-03 | Horne Timothy P | 9.1% |
| Schedule 13D/A, 2026-08-28 | Imperial Petroleum Inc. | 80.5% |
| Schedule 13G, 2026-08-19 | Jane Street Group, LLC | 7.2% |
| Schedule 13G/A, 2026-08-14 | S.H.N. Financial Investments LTD. | 0.4% |
| Schedule 13G/A, 2026-08-14 | L1 Capital Global Opportunities Master Fund, LTD. | 1.7% |
| Schedule 13G, 2026-08-04 | Ascent Partners Fund LLC | 9.99% |
| Schedule 13G/A, 2026-08-03 | Alta Partners LLC | 8.2% |
| Schedule 13G, 2026-08-03 | Cvi Investments, Inc. | 9.9% |
Questions about who owns C3is Inc.
Who owns C3is Inc.?
On this page, 3 holders' latest ownership filings report 5% or more of C3is Inc.: Imperial Petroleum Inc. (80.5%, Schedule 13D/A, filed 2026-08-28), Cvi Investments, Inc. (9.9%, Schedule 13G, filed 2026-08-03) and Horne Timothy P (9.1%, Schedule 13G, filed 2026-09-03).
Who are the largest shareholders of C3is Inc.?
By the share each holder's latest filing reports, the largest holders of C3is Inc. on this page are Imperial Petroleum Inc. (80.5%), Cvi Investments, Inc. (9.9%) and Horne Timothy P (9.1%).
When did Imperial Petroleum Inc. buy into C3is Inc.?
The filings give report dates, not purchase dates. The earliest filing from Imperial Petroleum Inc. on this page is the Schedule 13D/A, filed 2026-08-28, reporting 80.5%. That earliest filing is itself an amendment, which updates an earlier report.
Is this an audit or a full list?
Neither. The ownership list on this page covers only Schedule 13D and 13G filings, which holders make once they own 5% or more of a class of shares (an amendment can report a stake that has since fallen below 5%); 12 such filings are shown here. It is not an audit and not a full cap table: holders who never reached 5% are not listed, and a stake can change after its latest filing.
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What the Full Report on C3is Inc. covers
The Short Answer
Which Company This Is
What They Do, And How The Money Works
Who Runs It, And How To Reach Them
The Money: Funding, Valuation, Runway
Who Pays Them, And Who They Are Up Against
Warning Bells
Sources
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Which insiders own C3is Inc. shares?
Directors, officers and holders of 10% or more report their shares on Forms 3, 4 and 5. Each line is the latest such report, largest holding first.
- , a director: 4,778 shares, 1,162 held directly and 3,616 indirectly (Form 3, 2026-03-18).
Shares only: the company's cover page does not give one share count for a single class, so no percentage is worked out.
How much has C3is Inc. raised?
Latest IPO step: C3is Inc. filed its final IPO prospectus, ticker CISS (424B4, 2026-07-28).
IPO filings: 424B4, 2026-07-28, F-1/A, 2026-07-23, F-1, 2026-07-22, 424B4, 2025-12-11, F-1/A, 2025-12-05; ticker CISS on Nasdaq Capital Market.
Keep reading
More on C3is Inc. and the records around it.
C3is Inc. elsewhere on the record
- 5%+ stake filings Nov 2026
Companies that share a holder
- HORNE TIMOTHY P also filed stake reports on 1 other company: WATTS WATER TECHNOLOGIES INC (Oct 2026)
- TOWERVIEW LLC also filed stake reports on 1 other company: STEALTHGAS INC. (Jul 2026)
- Evergreen Capital Management LLC also filed stake reports on 2 other companies: BlockchAIn Digital Infrastructure, Inc. (May 2026), Signing Day Sports, Inc. (Jan 2026)
Related pages
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https://mentionfox.com/who-owns/c3is