144 0001856565 XXXXXXXX LIVE 0001447362 CASTLE BIOSCIENCES INC 001-38984 1500 W. Parkwood Ave, Suite 400 Friendswood TX 77546 8667889007 KRISTEN OELSCHLAGER Officer Common Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

29911 617961.26 30329952 06/16/2026 NASDAQ Common 06/16/2026 Exercise of Stock Options Issuer N 4152 06/16/2026 Cash Common 12/31/2025 Restricted & Performance Stock Units Issuer N 25759 12/31/2025 N/A Y The securities to be sold will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment will be the dates of exercise/sale. The securities to be sold were acquired upon the vesting of restricted stock units & performance stock units during the period of 12/31/2025 through 03/04/2026. 06/16/2026 03/17/2026 /s/ Kristen Oelschlager