C3is Inc. filings document a foreign private issuer operating a dry bulk and tanker shipping business. Form 6-K reports provide formal records of unaudited operating and financial results, vessel acquisition agreements, charter and fleet information, and securities matters tied to the company's common shares on The Nasdaq Capital Market.
The filing record also covers capital-structure actions, including reverse stock splits, amendments to articles of incorporation, warrant exercise and adjustment provisions, Series A Convertible Preferred Stock adjustments, registered offerings and an at-the-market sales agreement. Registration-statement references and incorporated exhibits describe placement-agent agreements, prospectus supplements and share-based compensation registration matters.
C3is Inc. (CISS) has a new significant shareholder disclosure. Jane Street Group, LLC, together with its subsidiaries Jane Street Capital, LLC and Jane Street Global Trading, LLC, reports beneficial ownership of 937,330 shares of C3is Inc. common stock, representing 7.2% of the outstanding class. All of these shares are held with shared voting and dispositive power; none are held with sole power. Within this total, Jane Street Capital, LLC is reported to beneficially own 678,960 shares (5.2%) and Jane Street Global Trading, LLC 258,370 shares (2.0%). The filing identifies Jane Street Group, LLC as the parent holding company, with the two subsidiaries as the entities that acquired the securities.
C3is Inc. (CISS) implemented a one-for-40 reverse stock split of its common stock effective as of 11:59 p.m. Eastern time on August 18, 2026. The number of outstanding common shares was reduced from approximately 57.6 million to approximately 1.44 million, while the $0.01 par value and other terms of the common stock were unchanged. Shares began trading on a split-adjusted basis on the Nasdaq Capital Market on August 19, 2026 under the symbol CISS. No fractional shares were issued; holders instead received cash in lieu of fractional shares. Outstanding warrants and Series A Convertible Preferred Stock will be proportionately adjusted for exercise and conversion terms, with certain warrant exercise and conversion prices further adjusted to the lowest daily volume weighted average price over a specified 10-trading-day window around the effective date.
C3is Inc. announced a one-for-forty (1-for-40) reverse stock split of its common stock, par value $0.01 per share. The reverse split will take effect at 11:59 p.m. Eastern Time on August 18, 2026. The company’s common stock will begin trading on a split-adjusted basis on The Nasdaq Capital Market at the opening of trading on August 19, 2026. This corporate action is also incorporated by reference into the company’s existing Form S-8 and Form F-3 registration statements.
L1 Capital Global Opportunities Master Fund, Ltd. filed an amended Schedule 13G reporting beneficial ownership of 223,038 shares of C3is Inc. common stock, representing 1.7% of the outstanding class. The ownership consists of Series B-2, Series C-2 and other warrants to purchase common shares, all with sole voting and dispositive power and no shared power. The percentage is based on 13,082,612 C3is common shares outstanding as referenced in a July 28, 2026 prospectus. L1 Capital notes that its directors David Feldman and Joel Arber may be deemed beneficial owners under Rule 13d-3 but each disclaims beneficial ownership except to the extent of any pecuniary interest.
S.H.N. Financial Investments Ltd. reports its beneficial ownership in C3is Inc. as an amendment, now reflecting a position below 5% of the company’s common shares. The filing lists 46,719 Series D Warrants to purchase common shares, representing 0.4% of the class.
The percentage is calculated against 13,082,612 common shares outstanding, as referenced from a July 28, 2026 prospectus. S.H.N. holds sole voting and dispositive power over these 46,719 warrants. Nir Shamir, as Chief Executive Officer of S.H.N., may be deemed a beneficial owner but disclaims beneficial ownership for other purposes.
C3is Inc. received a large-holder report from a group of affiliated entities and individuals, including Ascent Partners Fund LLC, Dominion Capital entities, Eagle Claw Corp., Masada Group Holdings LLC, and three individuals. Together they report beneficial ownership of 1,610,566 shares of common stock, representing 9.99% of the class.
The stake reflects shares held directly by Ascent and shares issuable upon partial exercise of warrants, all subject to a 9.99% beneficial ownership “Blocker”. As of August 4, 2026, Ascent directly owns 502,813 shares, with up to 1,107,753 additional shares issuable under a warrant, constrained by the Blocker. The percentage calculation uses 13,082,612 shares outstanding as of the July 28, 2026 offering plus shares issued or issuable from warrant exercises. Voting and dispositive power over the 1,610,566 shares is reported on a shared basis among the reporting persons under a joint filing agreement.
Alta Partners LLC filed an amended Schedule 13G reporting beneficial ownership of C3is Inc. common stock. Alta Partners reports owning 1,168,303 shares, including 1,140,000 shares of common stock and 28,303 shares issuable upon exercise of warrants.
This position represents 8.198% of the outstanding common stock class. Alta Partners has sole voting and sole dispositive power over all 1,168,303 shares and no shared voting or dispositive power.
C3is Inc. received a Schedule 13G from CVI Investments, Inc. and Heights Capital Management, Inc. reporting beneficial ownership of 1,221,154 Shares of common stock, representing 9.9% of the class. The position consists of 980,000 Shares plus additional Shares issuable upon exercise of warrants.
The warrants are subject to a 9.99% beneficial ownership cap, preventing exercises that would push combined ownership above that level under Section 13(d) rules. Based on company information, there were 11,982,612 Shares outstanding (excluding Shares underlying the warrants) as of the completion of the referenced offering. Heights Capital, as investment manager to CVI, may be deemed to share voting and dispositive power, though both Reporting Persons disclaim beneficial ownership beyond their pecuniary interest.
C3is Inc. has a significant shareholder group led by Lind Global Fund III LP, Lind Global Partners III LLC, and Jeff Easton, which together report beneficial ownership of 1,325,482 common shares of C3is Inc. common stock, representing 9.99% of the outstanding class.
The position is held through 1,140,000 units, with each unit consisting of one common share and one warrant to purchase an additional common share. The warrants contain a conversion limitation that prevents exercises which would increase the holders’ beneficial ownership above 9.99%, effectively capping voting and dispositive power at that level.
Imperial Petroleum Inc., a Marshall Islands corporation, has filed Amendment No. 12 to its beneficial ownership report on the common stock of C3is Inc. Imperial Petroleum reports beneficial ownership of 28,846,153 shares of common stock, representing 68.8% of the outstanding class, with sole voting and dispositive power over these shares.
The amendment reflects an adjustment of the conversion price of C3is’s 5.0% Series A Cumulative Convertible Perpetual Preferred Stock to $0.52, triggered by C3is’s sale of common stock in a registered offering described in a prospectus dated July 28, 2026, and an updated total share count. Imperial Petroleum acquired its position in connection with a spin-off distribution and intends to review its investment on an ongoing basis, with flexibility to buy, hold, or sell shares and to consider a wide range of potential corporate actions. Harry N. Vafias, Imperial Petroleum’s Chairman, Chief Executive Officer and President, serves as Non-Executive Chairman of C3is and beneficially owns 753 C3is shares, while two other shared directors hold no C3is shares.