X0609 4 2026-06-01 true 0001829802 Sensei Biotherapeutics, Inc. SNSE 0001843594 Peyer James false 228 PARK AVENUE S. #66643 NEW YORK NY 10003 false false true true See remarks below false Common Stock 2026-06-01 4 S false 24524 20.00 D 130618 D Common Stock 2026-06-01 4 S false 476 21.14 D 130142 D The price reported in Column 4 is a weighted average price. The prices sold ranged from $20.00 to $21.00. The reporting person will provide the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. /s/ James Peyer 2026-06-01