X0609 4 2026-03-26 1 0001829802 Sensei Biotherapeutics, Inc. SNSE 0001273087 MILLENNIUM MANAGEMENT LLC false 399 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001783647 ICS OPPORTUNITIES II LLC false C/O MILLENNIUM MANAGEMENT LLC 399 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001446830 MILLENNIUM GROUP MANAGEMENT LLC false 399 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0001017456 ENGLANDER ISRAEL A false C/O MILLENNIUM MANAGEMENT LLC 399 PARK AVENUE NEW YORK NY 10022 0 0 1 0 0 Common Stock 2026-03-26 4 P 0 778 27.2267 A 131370 I See footnote Common Stock 2026-03-26 4 P 0 1327 27.9467 A 131370 I See footnote Common Stock 2026-03-26 4 P 0 2601 28.8539 A 131370 I See footnote Common Stock 2026-03-26 4 P 0 1025 29.9788 A 131370 I See footnote Common Stock 2026-03-26 4 S 0 583 26.8797 D 131370 I See footnote Common Stock 2026-03-26 4 S 0 1274 28.6882 D 131370 I See footnote Common Stock 2026-03-27 4 P 0 10643 26.2933 A 142360 I See footnote Common Stock 2026-03-27 4 P 0 4384 27.2826 A 142360 I See footnote Common Stock 2026-03-27 4 P 0 294 28.1301 A 142360 I See footnote Common Stock 2026-03-27 4 S 0 469 26.7652 D 142360 I See footnote Common Stock 2026-03-27 4 S 0 36 27.3690 D 142360 I See footnote Common Stock 2026-03-30 4 P 0 2992 25.0784 A 145678 I See footnote Common Stock 2026-03-30 4 P 0 4995 25.9900 A 145678 I See footnote Common Stock 2026-03-30 4 P 0 1176 26.7000 A 145678 I See footnote Common Stock 2026-03-30 4 P 0 370 27.6800 A 145678 I See footnote Common Stock 2026-03-30 4 S 0 518 25.8501 D 145678 I See footnote Common Stock 2026-03-30 4 S 0 370 27.6800 D 145678 I See footnote Represents volume-weighted average price ("VWAP") of purchases of 778 shares of common stock ("Common Stock"), par value $0.0001 per share, of Sensei Biotherapeutics, Inc. (the "Company") on March 26, 2026 at prices ranging from $26.66 to $27.62. Upon request by the Commission staff, the Company, or a security holder of the Company, the reporting persons will provide full information regarding the number of shares purchased or sold by the reporting person at each separate price within each range represented by a VWAP disclosed herein. In each case, the number of shares of the Company's Common Stock disclosed in column 5 is the number of shares of the Company's Common Stock beneficially owned by Millennium Management LLC at the conclusion of the transactions on the date disclosed in the corresponding entry in column 2. The transactions in the Company's Common Stock reported herein were made by ICS Opportunities II LLC or other trading entities, in each case subject to voting control and investment discretion by Millennium Management LLC, Millennium Group Management LLC (the managing member of Millennium Management LLC) and Israel A. Englander (the sole voting trustee of the managing member of Millennium Group Management LLC). Each reporting person disclaims beneficial ownership of the shares of the Company's Common Stock disclosed herein except to the extent of such reporting person's pecuniary interest therein, if any. Represents VWAP of purchases of 1,327 shares of the Company's Common Stock on March 26, 2026 at prices ranging from $27.70 to $28.4163. Represents VWAP of purchases of 2,601 shares of the Company's Common Stock on March 26, 2026 at prices ranging from $28.7072 to $29.51. Represents VWAP of purchases of 1,025 shares of the Company's Common Stock on March 26, 2026 at prices ranging from $29.79 to $30.105. Represents VWAP of sales of 583 shares of the Company's Common Stock on March 26, 2026 at prices ranging from $26.68 to $27.4650. Represents VWAP of sales of 1,274 shares of the Company's Common Stock on March 26, 2026 at prices ranging from $28.07 to $28.7651. Represents VWAP of purchases of 10,643 shares of the Company's Common Stock on March 27, 2026 at prices ranging from $25.9197 to $26.88. Represents VWAP of purchases of 4,384 shares of the Company's Common Stock on March 27, 2026 at prices ranging from $26.9750 to $27.68. Represents VWAP of purchases of 294 shares of the Company's Common Stock on March 27, 2026 at prices ranging from $28.10 to $28.60. Represents VWAP of sales of 469 shares of the Company's Common Stock on March 27, 2026 at prices ranging from $26.21 to $26.95. Represents VWAP of sales of 36 shares of the Company's Common Stock on March 27, 2026 at prices ranging from $27.2322 to $27.68. Represents VWAP of purchases of 2,992 shares of the Company's Common Stock on March 30, 2026 at prices ranging from $24.495 to $25.1856. Represents VWAP of purchases of 4,995 shares of the Company's Common Stock on March 30, 2026 at prices ranging from $25.50 to $26.48. Represents VWAP of purchases of 1,176 shares of the Company's Common Stock on March 30, 2026 at prices ranging from $26.50 to $26.90. Represents purchases of 370 shares of the Company's Common Stock on March 30, 2026 at $27.68 per share. Represents VWAP of sales of 518 shares of the Company's Common Stock on March 30, 2026 at prices ranging from $25.13 to $26.0734. Represents sales of 370 shares of the Company's Common Stock on March 30, 2026 at $27.68 per share. Assuming, without conceding, the application of Section 16(b) of the Securities Exchange Act of 1934, the reporting persons have disgorged to the Company all amounts that could be deemed profit realized by them from the transactions in the Company's Common Stock reported on this Form 4 and the other two statements on Form 4 filed by Millennium Management LLC on the same date. MILLENNIUM MANAGEMENT LLC: By: /s/ Gil Raviv, Global General Counsel 2026-05-14 ICS OPPORTUNITIES II LLC, By: Millennium Management LLC, its Investment Manager: By: /s/ Gil Raviv, Global General Counsel 2026-05-14 MILLENNIUM GROUP MANAGEMENT LLC: By: /s/ Gil Raviv, Global General Counsel 2026-05-14 /s/ Israel A. Englander 2026-05-14