144 0001838061 XXXXXXXX LIVE 0001789972 CULLINAN THERAPEUTICS, INC. 001-39856 One Main Street, Suite 1350 Cambridge MA 02142 6174104650 JENNIFER MICHAELSON Officer COMMON Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

8000 101440.00 58227593 01/06/2025 NASDAQ Common 12/16/2019 Restricted Stock Units Issuer N 4523 12/16/2019 N/A Common 01/06/2025 Exercise of Stock Options Issuer N 3477 01/06/2025 Cash N JENNIFER MICHAELSON

One Main Street, Suite 1350 Cambridge MA 02142

Common 12/18/2024 4693 53547.13 JENNIFER MICHAELSON

One Main Street, Suite 1350 Cambridge MA 02142

Common 12/12/2024 3489 43682.28 10b5-1 Sales for JENNIFER MICHAELSON

One Main Street, Suite 1350 Cambridge MA 02142

COMMON 11/05/2024 8000 125102.80 The securities to be sold were acquired upon the vesting of restricted stock units during the period of 12/16/2023 through 12/17/2023 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. 01/06/2025 01/05/2024 /s/ Jennifer Michaelson