George Economou - 16 Mar 2026 SCHEDULE 13D/A Report for Seanergy Maritime Holdings Corp. Common Shares, par value $0.0001 per share (SHIP)

Filing manager: George Economou
Reporting owner: Sphinx Investment Corp.
Security: Seanergy Maritime Holdings Corp. Common Shares, par value $0.0001 per share
Beneficially owned shares: 1,848,534 shares
Large-stake signal: Form
SCHEDULE 13D/A
Active or control-oriented beneficial ownership filing.
Ownership
8.8%
Beneficial ownership of this reported class.
Shares
1,848,534 shares
Shares beneficially owned as disclosed.
Event date
16 Mar 2026
Date tied to the ownership event or amendment.
Accepted by SEC
16 Mar 2026
EDGAR acceptance date.
How to read this large-stake filing
Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
Compare this filing with the holder history and issuer page before treating the percentage as a current position.
Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
Class ownership: 8.8%
Symbol: SHIP
Shares outstanding: 21,006,068 shares
SEC form: SCHEDULE 13D/A
Accepted by SEC: 16 Mar 2026, 08:40:20 UTC
Event date: 16 Mar 2026
Source filing: View source filing

Key filing fact

George Economou disclosed 8.8% ownership in Seanergy Maritime Holdings Corp. Common Shares, par value $0.0001 per share (SHIP) on 16 Mar 2026.

Key facts

George Economou filed SCHEDULE 13D/A for Seanergy Maritime Holdings Corp. Common Shares, par value $0.0001 per share (SHIP).
Disclosed ownership: 8.8%.
Date of event: 16 Mar 2026.

This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.

Backed by Schedule 13D/13G

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

Reporting persons

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

Name	Ownership	Shares owned	Shared voting power	Signature	Title	CIK
Sphinx Investment Corp.	8.8%	1,848,534	1,848,534	Kleanthis Costa Spathias	By: Levante Services Limited, By: Kleanthis Costa Spathias, Director	0001990966
Maryport Navigation Corp.	8.8%	1,848,534	1,848,534	Kleanthis Costa Spathias	By: Levante Services Limited, By: Kleanthis Costa Spathias, Director
George Economou	8.8%	1,848,534	1,848,534	George Economou	George Economou	0001308557

CIK / CUSIP context first

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