SCHEDULE 13G/A

Rubico Inc.

Common Stock, $0.01 par value per share · CUSIP: Y1250N107

Event date: 2025-12-31

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

• Arena Investors, LP

  Shares: 0.00 · Class: 0.0%

• Arena Investors GP, LLC

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities (Offshore) Master, LP

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Fund (Offshore) II GP, LP

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Fund (Offshore) GP, LLC

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Parallel Investor Vehicle III US, LP

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Parallel Investor Vehicle III GP, LLC

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Partners III, LP

  Shares: 0.00 · Class: 0.0%

• Arena Special Opportunities Partners III GP, LLC

  Shares: 0.00 · Class: 0.0%

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