13D·WATCH Activist + Insider Intelligence Live feed Blog About Pricing
ISSUER PROFILE · CIK 0001951067 · CUSIP Y18284409

C3is Inc.CISS

11 13D/G filings 6 distinct filers 0 insider transactions (365d)

Post-Filing Returns · across 5 activist filings on this issuer

Median 30d
-20.4%
avg -13.5%
Median 60d
-28.2%
avg -28.8%
Median 90d
-90.1%
avg -80.8%
Median 180d
-98.3%
avg -87.6%

Returns measured from each activist filing's date_of_event, split + dividend adjusted via Yahoo Finance.

Cross-Reference Snapshot

Activist filings
11
4 SCHEDULE 13G · 3 SCHEDULE 13D/A · 4 SCHEDULE
Distinct filers
6
multi-activist cluster
Insiders (365d)
0
0 buys · 0 sales
Latest short DTC
1.00
as of 2026-08-31

13D/G Filings Timeline · 11 total

FiledFormFilerStakeSharesIntent
2026-09-03 SCHEDULE 13G HORNE TIMOTHY P view →
2026-08-28 SCHEDULE 13D/A Imperial Petroleum Inc./Marshall Islands 80.50% 6,136,475 view →
2026-08-19 SCHEDULE 13G JANE STREET GROUP, LLC view →
2026-08-04 SCHEDULE 13G Ascent Partners Fund LLC view →
2026-07-30 SCHEDULE 13D/A Imperial Petroleum Inc./Marshall Islands 68.80% 28,846,153 view →
2026-06-24 SCHEDULE 13D/A Imperial Petroleum Inc./Marshall Islands 82.90% 7,171,543 view →
2026-05-18 SCHEDULE 13G TOWERVIEW LLC view →
2025-10-10 SCHEDULE Imperial Petroleum Inc./Marshall Islands 68.80% 6,000,000 view →
2025-10-10 SCHEDULE Flawless Management Inc. 3.70% 100,577 view →
2025-10-01 SCHEDULE Flawless Management Inc. 6.30% 100,577 view →
2025-01-14 SCHEDULE Imperial Petroleum Inc./Marshall Islands 73.10% 11,532,251 view →

FINRA Short Interest History

SettlementShort InterestDays to Cover% Δ vs prior
2026-08-31 93,408 1.00 -83.0%
2026-08-14 551,009 1.00 -80.8%
2026-07-31 2,866,583 1.00 +4600.9%
2026-07-15 60,980 1.00 +69.4%
2026-06-30 36,007 1.00 -56.4%
2026-06-15 82,532 1.00 +69.8%
2026-05-29 48,614 1.00 -53.3%
2026-05-15 104,053 3.08 +22.4%
2026-04-30 84,980 1.11 +699.4%
2026-04-15 10,631 1.00 -81.8%
2026-03-31 58,387 1.00 -3.7%
2026-03-13 60,614 1.00 -75.9%

Alert me when any activist files on C3is Inc.

Free. We email you when criteria match. One-click unsubscribe in every email.

Track every activist who touches this name.

Custom alerts · full feed · daily intelligence · API. From $49/mo.

See pricing →