Reporting Manager
Imperial Petroleum Inc.
Symbol
CISS
Shares outstanding
20,458,265 shares
Disclosed Ownership
12,500,000 shares
Ownership
61%
Form type
SCHEDULE 13D/A
Filing time
15 Dec 2025, 06:05:17 UTC
Date of event
12 Dec 2025
Previous filing
10 Oct 2025
Next filing
30 Dec 2025

Key filing fact

Imperial Petroleum Inc./Marshall Islands disclosed 61% ownership in C3is Inc. Common Stock, par value $0.01 per share (CISS) on 12 Dec 2025.

Key facts

  • Imperial Petroleum Inc./Marshall Islands filed SCHEDULE 13D/A for C3is Inc. Common Stock, par value $0.01 per share (CISS).
  • Disclosed ownership: 61%.
  • Date of event: 12 Dec 2025.

Change

  • Previous schedule filing date: 10 Oct 2025.
  • Current filing was accepted on 15 Dec 2025, 06:05.

Research use

  • This page explains what this Schedule 13D/13G filing tells you before manager-level rows.
  • You can verify ownership claims directly against the original SEC filing.

Evidence

Backed by Schedule 13D/13G

Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.

See Original Filing

Reporting persons

Reporting managers (1)

Names, ownership, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.

Name Ownership Shares Owned sole voting power shared voting power Signature Title CIK
Imperial Petroleum Inc. 61% 12,500,000 12,500,000 0 Harry N. Vafias Chief Executive Officer 0001876581
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