Form 4 Filing for Brilliant Earth Group, Inc.

This filing details transactions by Mainsail entities related to Brilliant Earth Group, Inc. On August 24, 2026, Mainsail Partners III, L.P., Mainsail Co-Investors III, L.P., and Mainsail Incentive Program, LLC acquired LLC Units exchangeable for Class A Common Stock and Class B Common Stock. These acquisitions, with a deemed value of $18,096, are considered matchable against prior sales, resulting in a disgorged profit of $2,033 to the issuer. The reporting persons, including Mainsail GP III, LLC and Mainsail Management Company, LLC, disclaim beneficial ownership beyond their pecuniary interests. Post-transaction, the entities collectively hold 31,848,071 shares of Class B Common Stock and associated LLC Units.