C3is Inc.

Symbol
CISS on Nasdaq
Entity
Company
Business address
331 Kifissias Avenue, Erithrea, 14561 Athens, Greece
Phone
011-30-210-625-0001
State of incorporation
Marshall Islands
Fiscal year end
December 31
Category
Non-accelerated filer
Emerging growth company
All SEC filings
View on sec.gov
C3is Inc. has filed 168 SEC EDGAR filings since 12/7/2022

Latest Filings

Form type Document Filing Description Filing date Reporting date File number(s)
F-1 Open Document | Data Open Filing F-1 Sep 3, 2025 333-290011
424B3 Open Document Open Filing 424B3 Sep 2, 2025 333-272939
424B3 Open Document Open Filing 424B3 Sep 2, 2025 333-276868
424B3 Open Document Open Filing 424B3 Sep 2, 2025 333-276430
6-K Open Document Open Filing 6-K Sep 2, 2025 Sep 2, 2025 001-41717
6-K Open Document Open Filing 6-K Aug 29, 2025 Aug 29, 2025 001-41717
DRS Open Document Open Filing Jul 21, 2025 377-08236
6-K Open Document Open Filing 6-K Jun 25, 2025 Jun 25, 2025 001-41717
424B3 Open Document Open Filing 424B3 May 16, 2025 333-276430
424B3 Open Document Open Filing 424B3 May 16, 2025 333-272939
424B3 Open Document Open Filing 424B3 May 16, 2025 333-276868
6-K Open Document Open Filing 6-K May 16, 2025 May 16, 2025 001-41717
EFFECT Open Document Open Filing May 5, 2025 333-276868
EFFECT Open Document Open Filing May 5, 2025 333-276430
EFFECT Open Document Open Filing May 5, 2025 333-272939
POS AM Open Document Open Filing POS AM Apr 30, 2025 333-276430
POS AM Open Document Open Filing POS AM Apr 30, 2025 333-272939
POS AM Open Document Open Filing POS AM Apr 30, 2025 333-276868
20-F Open Document | Data Open Filing 20-F Apr 28, 2025 Dec 31, 2024 001-41717
SCHEDULE 13D/A Open Document Open Filing Apr 15, 2025 005-94125
424B3 Open Document Open Filing 424B3 Apr 4, 2025 333-272939
424B3 Open Document Open Filing 424B3 Apr 4, 2025 333-276868
424B3 Open Document Open Filing 424B3 Apr 4, 2025 333-276430
6-K Open Document Open Filing 6-K Apr 4, 2025 Apr 4, 2025 001-41717
424B3 Open Document Open Filing 424B3 Apr 2, 2025 333-272939
424B3 Open Document Open Filing 424B3 Apr 2, 2025 333-276868
424B3 Open Document Open Filing 424B3 Apr 2, 2025 333-276430
6-K Open Document Open Filing 6-K Apr 2, 2025 Apr 2, 2025 001-41717
424B3 Open Document Open Filing 424B3 Mar 12, 2025 333-272939
424B3 Open Document Open Filing 424B3 Mar 12, 2025 333-276868
424B3 Open Document Open Filing 424B3 Mar 12, 2025 333-276430
6-K Open Document Open Filing 6-K Mar 12, 2025 Mar 12, 2025 001-41717
EFFECT Open Document Open Filing Mar 6, 2025 333-285135
CORRESP Open Document Open Filing Mar 4, 2025
UPLOAD Open Document Open Filing Mar 3, 2025 333-285135
F-3 Open Document Open Filing F-3 Feb 21, 2025 333-285135
6-K Open Document Open Filing 6-K Feb 21, 2025 Feb 21, 2025 001-41717
6-K Open Document Open Filing 6-K Feb 18, 2025 Feb 18, 2025 001-41717
SCHEDULE 13G/A Open Document Open Filing Feb 14, 2025 005-94125
SCHEDULE 13D/A Open Document Open Filing Jan 14, 2025 005-94125
424B3 Open Document Open Filing 424B3 Jan 2, 2025 333-276868
424B3 Open Document Open Filing 424B3 Jan 2, 2025 333-276430
424B3 Open Document Open Filing 424B3 Jan 2, 2025 333-272939
6-K Open Document Open Filing 6-K Jan 2, 2025 Jan 2, 2025 001-41717
EFFECT Open Document Open Filing Dec 13, 2024 333-276430
EFFECT Open Document Open Filing Dec 13, 2024 333-276868
EFFECT Open Document Open Filing Dec 13, 2024 333-272939
POS AM Open Document Open Filing POS AM Dec 10, 2024 333-272939
POS AM Open Document Open Filing POS AM Dec 10, 2024 333-276868
POS AM Open Document Open Filing POS AM Dec 10, 2024 333-276430
424B3 Open Document Open Filing 424B3 Nov 19, 2024 333-272939
424B3 Open Document Open Filing 424B3 Nov 19, 2024 333-276868
424B3 Open Document Open Filing 424B3 Nov 19, 2024 333-276430
6-K Open Document Open Filing 6-K Nov 19, 2024 Nov 19, 2024 001-41717
424B3 Open Document Open Filing 424B3 Sep 30, 2024 333-272939
424B3 Open Document Open Filing 424B3 Sep 30, 2024 333-276868
424B3 Open Document Open Filing 424B3 Sep 30, 2024 333-276430
6-K Open Document | Data Open Filing 6-K Sep 30, 2024 Jun 30, 2024 001-41717
SC 13D/A Open Document Open Filing SC 13D/A Sep 18, 2024 005-94125
6-K Open Document Open Filing 6-K Aug 30, 2024 Aug 30, 2024 001-41717
6-K Open Document Open Filing 6-K Aug 23, 2024 Aug 23, 2024 001-41717
SC 13D/A Open Document Open Filing SC 13D/A Jun 24, 2024 005-94125
424B3 Open Document Open Filing 424B3 May 28, 2024 333-276868
424B3 Open Document Open Filing 424B3 May 28, 2024 333-276430
424B3 Open Document Open Filing 424B3 May 28, 2024 333-272939
6-K Open Document Open Filing 6-K May 28, 2024 May 28, 2024 001-41717
SC 13G Open Document Open Filing SC 13G May 24, 2024 005-94125
SC 13D Open Document Open Filing SC 13D May 20, 2024 005-94125
EFFECT Open Document Open Filing May 8, 2024 333-272939
EFFECT Open Document Open Filing May 8, 2024 333-276430
EFFECT Open Document Open Filing May 8, 2024 333-276868
SC 13D/A Open Document Open Filing SC 13D/A May 1, 2024 005-94125
POS AM Open Document Open Filing POS AM May 1, 2024 333-276868
POS AM Open Document Open Filing POS AM May 1, 2024 333-276430
POS AM Open Document Open Filing POS AM May 1, 2024 333-272939
20-F Open Document | Data Open Filing 20-F Apr 30, 2024 Dec 31, 2023 001-41717
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-276868
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-276430
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-272939
6-K Open Document Open Filing 6-K Apr 12, 2024 Apr 12, 2024 001-41717
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-276868
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-276430
424B3 Open Document Open Filing 424B3 Apr 12, 2024 333-272939
6-K Open Document Open Filing 6-K Apr 12, 2024 Apr 12, 2024 001-41717
424B3 Open Document Open Filing 424B3 Mar 26, 2024 333-276868
424B3 Open Document Open Filing 424B3 Mar 26, 2024 333-276430
424B3 Open Document Open Filing 424B3 Mar 26, 2024 333-272939
6-K Open Document Open Filing 6-K Mar 26, 2024 Mar 26, 2024 001-41717
SC 13G Open Document Open Filing SCHEDULE 13G Mar 25, 2024 005-94125
SC 13D/A Open Document Open Filing SC 13D/A Mar 20, 2024 005-94125
424B3 Open Document Open Filing 424B3 Mar 19, 2024 333-276868
424B3 Open Document Open Filing 424B3 Mar 19, 2024 333-276430
424B3 Open Document Open Filing 424B3 Mar 19, 2024 333-272939
6-K Open Document Open Filing 6-K Mar 19, 2024 Mar 19, 2024 001-41717
424B3 Open Document Open Filing 424B3 Mar 15, 2024 333-276868
424B3 Open Document Open Filing 424B3 Mar 15, 2024 333-276430
424B3 Open Document Open Filing 424B3 Mar 15, 2024 333-272939
6-K Open Document Open Filing 6-K Mar 15, 2024 Mar 15, 2024 001-41717
424B4 Open Document Open Filing 424B4 Mar 15, 2024 333-276868
EFFECT Open Document Open Filing Mar 14, 2024 333-276868
CORRESP Open Document Open Filing Mar 14, 2024
CORRESP Open Document Open Filing Mar 14, 2024
CORRESP Open Document Open Filing Mar 14, 2024
CORRESP Open Document Open Filing Mar 14, 2024
CORRESP Open Document Open Filing Mar 11, 2024
CORRESP Open Document Open Filing Mar 11, 2024
CORRESP Open Document Open Filing Feb 23, 2024
F-1/A Open Document Open Filing F-1/A Feb 23, 2024 333-276868
UPLOAD Open Document Open Filing Feb 22, 2024 333-276868
424B3 Open Document Open Filing 424B3 Feb 22, 2024 333-276430
424B3 Open Document Open Filing 424B3 Feb 22, 2024 333-272939
6-K Open Document Open Filing FORM 6-K Feb 22, 2024 Feb 22, 2024 001-41717
SC 13G Open Document Open Filing 13-G Feb 9, 2024 005-94125
F-1 Open Document Open Filing F-1 Feb 5, 2024 333-276868
SC 13G Open Document Open Filing SCHEDULE 13G Jan 29, 2024 005-94125
SC 13G Open Document Open Filing SCHEDULE 13G Jan 29, 2024 005-94125
SC 13D/A Open Document Open Filing SC 13D/A Jan 24, 2024 005-94125
SC 13D/A Open Document Open Filing SC 13D/A Jan 24, 2024 005-94125
424B3 Open Document Open Filing 424B3 Jan 23, 2024 333-272939
6-K Open Document Open Filing 6-K Jan 23, 2024 Jan 23, 2024 001-41717
424B4 Open Document Open Filing 424B4 Jan 22, 2024 333-276430
F-1MEF Open Document Open Filing F-1MEF Jan 19, 2024 333-276597
EFFECT Open Document Open Filing Jan 18, 2024 333-276430
CORRESP Open Document Open Filing Jan 17, 2024
CORRESP Open Document Open Filing Jan 17, 2024
UPLOAD Open Document Open Filing Jan 16, 2024 333-276430
F-1 Open Document Open Filing F-1 Jan 8, 2024 333-276430
SC 13D Open Document Open Filing SC 13D Nov 16, 2023 005-94125
424B3 Open Document Open Filing 424B3 Nov 6, 2023 333-272939
6-K Open Document Open Filing 6-K Nov 6, 2023 Nov 6, 2023 001-41717
DRS Open Document Open Filing Sep 29, 2023 377-06902
424B3 Open Document Open Filing 424B3 Sep 29, 2023 333-272939
6-K Open Document Open Filing 6-K Sep 29, 2023 Sep 29, 2023 001-41717
6-K Open Document Open Filing 6-K Sep 8, 2023 Sep 8, 2023 001-41717
424B3 Open Document Open Filing 424B3 Aug 25, 2023 333-272939
6-K Open Document Open Filing 6-K Aug 25, 2023 Aug 25, 2023 001-41717
SC 13D Open Document Open Filing SC 13D Jul 28, 2023 005-94125
S-8 Open Document Open Filing S-8 Jul 18, 2023 333-273306
424B3 Open Document Open Filing 424B3 Jul 17, 2023 333-272939
6-K Open Document Open Filing 6-K Jul 17, 2023 Jul 17, 2023 001-41717
424B3 Open Document Open Filing 424B3 Jul 5, 2023 333-272939
6-K Open Document Open Filing 6-K Jul 5, 2023 Jul 5, 2023 001-41717
424B4 Open Document Open Filing 424B4 Jul 3, 2023 333-272939
EFFECT Open Document Open Filing Jun 30, 2023 333-272939
CORRESP Open Document Open Filing Jun 28, 2023
CORRESP Open Document Open Filing Jun 28, 2023
F-1 Open Document Open Filing F-1 Jun 26, 2023 333-272939
UPLOAD Open Document Open Filing Jun 26, 2023
6-K Open Document Open Filing 6-K Jun 23, 2023 Jun 23, 2023 001-41717
DRS Open Document Open Filing Jun 14, 2023 377-06747
EFFECT Open Document Open Filing Jun 12, 2023 333-271228
424B1 Open Document Open Filing 424B1 Jun 12, 2023 333-271228
CERT Open Document Open Filing Jun 12, 2023 001-41717
CORRESP Open Document Open Filing Jun 8, 2023
8-A12B Open Document Open Filing 8-A12B Jun 8, 2023 001-41717
CORRESP Open Document Open Filing Jun 6, 2023
F-1/A Open Document Open Filing F-1/A Jun 6, 2023 333-271228
UPLOAD Open Document Open Filing Jun 1, 2023
CORRESP Open Document Open Filing May 17, 2023
F-1/A Open Document Open Filing F-1/A May 17, 2023 333-271228
UPLOAD Open Document Open Filing Apr 28, 2023
CORRESP Open Document Open Filing Apr 12, 2023
F-1 Open Document Open Filing F-1 Apr 12, 2023 333-271228
UPLOAD Open Document Open Filing Feb 13, 2023
DRSLTR Open Document Open Filing Jan 25, 2023
DRS/A Open Document Open Filing Jan 25, 2023 377-06490
UPLOAD Open Document Open Filing Jan 3, 2023
DRS Open Document Open Filing Dec 7, 2022 377-06490