X0609 4 2026-09-02 0 0001819796 GCM Grosvenor Inc. GCMG 0001684847 SULLIVAN KATHLEEN PATRICIA false C/O GCM GROSVENOR INC. 900 NORTH MICHIGAN AVENUE, SUITE 1100 CHICAGO IL 60611 0 1 0 0 Principal Accounting Officer 0 Class A Common Stock 2026-09-02 4 S 0 24963 13.1538 D 59832 D Class A Common Stock 2026-09-03 4 S 0 15037 13.1648 D 44795 D The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.0500 to $13.4500, inclusive. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.0200 to $13.3500, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (1) and (2) to this Form 4. /s/ Burke Montgomery, Attorney-in-Fact 2026-09-03