SCHEDULE 13G

SEACOR Marine Holdings Inc

Common Stock, par value $.01 per share · CUSIP: 78413P101

Event date: 2026-09-30

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• P. Oppenheimer Investment Parternship, LP

  Shares: 530,010 · Class: 1.95%

• Oppenheimer-Close Investment Partnership, LP

  Shares: 147,961 · Class: 0.55%

• Oppenheimer + Close, LLC

  Shares: 705,086 · Class: 2.6%

• Oppvest, LLC

  Shares: 677,971 · Class: 2.5%

• Carl K. Oppenheimer

  Shares: 1,383,057 · Class: 5.1%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.