X0202 SCHEDULE 13D 0001486180 XXXXXXXX LIVE equity 05/13/2026 false 0001287098 57777K106 MAXCYTE, INC.

9713 KEY WEST AVENUE, SUITE 400 ROCKVILLE MD 20850

Nusayhah Ghaboos 02033275025 30 Coleman Street London X0 EC2R 5AL 0001486180 N RIVER GLOBAL INVESTORS LLP OO N X0 6529027.00 0.00 6529027.00 0.00 6529027.00 N 6.1 IV equity MAXCYTE, INC. 9713 KEY WEST AVENUE, SUITE 400 ROCKVILLE MD 20850 River Global Investors LLP 30 Coleman Street, London, EC2R 5AL, United Kingdom Investment Firm 30 Coleman Street, London, EC2R 5AL, United Kingdom No No United Kingdom The Shares were acquired using investment capital of the Funds managed by the Reporting Persons. (a) The acquisition by any person of additional securities of the issuer, or the disposition of securities of the issuer; 6,529,027 shares 6.0950% Ownership 6,529,027 shares 1) River Global Investors LLP 2) 05/13/2026 3) 31,000 shares at 1.115 and 619,000 shares at 1.1142 5) The transactions were effected through brokers in ordinary open-market transactions. Not applicable. Not applicable. Not applicable. Not applicable. RIVER GLOBAL INVESTORS LLP N.Ghaboos 05/14/2026