144 0001856565 XXXXXXXX LIVE 0001447362 Castle Biosciences, Inc. 001-38984 505 S. Friendswood Drive, Suite 401 Friendswood TX 77546 866-788-9007 Kristen M. Oelschlager Officer Common Stock J.P. Morgan Securities LLC

270 Park Avenue, 10th Floor New York NY 10017

18932 657698 29188659 11/11/2025 NASDAQ Common Stock 12/29/2023 ISO Issuer N 8000 12/29/2023 Cash Common Stock 04/05/2019 Founder Shares Issuer N 10932 04/05/2019 Cash N Kristen M. Oelschlager

C/o Castle Biosciences, Inc. 505 S. Friendswood Drive, Suite 401 Friendswood TX 77546

Common Stock 08/27/2025 12677 279140 Kristen M. Oelschlager

C/o Castle Biosciences, Inc. 505 S. Friendswood Drive, Suite 401 Friendswood TX 77546

Common Stock 10/31/2025 12678 317503 The Fritz Shorter Trust

C/o Castle Biosciences, Inc. 505 S. Friendswood Drive, Suite 401 Friendswood TX 77546

Common Stock 08/27/2025 18007 390595 Sales that were executed on 11/11/25 are being reported on this Form 144 filed on 11/12/25 given the EDGAR system was not accepting filings on 11/11/25 in observance of the federal holiday. 11/12/2025 03/06/2025 /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Kristen M. Oelschlager.