C3IS INC

Historical 13F Holders

Symbol
CISS
CUSIP
Y18284177
All holders as of
Q1 2026
Type
Equity
Class
COM NEW
Reported Value, Excluding Options
Total Filings

13D/G Filers

Investors who own more than 5% of a class must file a Schedule 13D or 13G. Each filer's latest filing for Y18284177 since 12/18/2024, largest first.

Filer % of Class Filed
Imperial Petroleum Inc./Marshall Islands 13D/A 81.9% 2/4/2026
Event 2/2/2026
Ayrton Capital LLC 13G
10.0% 2/11/2026
Event 12/31/2025
Under 5%, checked the "5 percent or less" box, or amended by a later filing (1)
Alta Partners LLC 13G
Amended under CUSIP Y18284409 on 10/5/2026
5.2% 2/27/2026
Event 2/27/2026

13F Holders by Quarter

Period Filings Shares, Excl. Options Value, Excl. Options
2026 Q1 3 88.5 k $72.9 k