X0306 4 2022-01-03 0 0001720580 Adicet Bio, Inc. ACET 0001823901 Jakobovits Aya C/O ADICET BIO, INC. 200 CLARENDON STREET, FLOOR 6 BOSTON MA 02116 1 0 0 0 Common Stock 2022-01-03 4 S 0 6000 18.0208 D 366343 I See Footnote Common Stock 2022-01-03 4 S 0 6000 18.0218 D 366345 I See Footnote Common Stock 2022-01-05 4 S 0 2000 16.932 D 364343 I See Footnote Common Stock 2022-01-05 4 S 0 2000 16.8995 D 364345 I See Footnote Common Stock 2022-02-09 4 S 0 4000 14.0294 D 360343 I See Footnote Common Stock 2022-02-09 4 S 0 4000 14.0303 D 360345 I See Footnote Common Stock 138076 I See Footnote These sales were effected pursuant to Rule 10b5-1 trading plans previously adopted by the Reporting Person. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $18.00 to $18.11. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. Shares held in a trust of which Dr. Jakobovits' spouse is the trustee and Dr. Jakobovits' daughter is the beneficiary. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $18.00 to $18.07. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. Shares held in a trust of which Dr. Jakobovits' spouse is the trustee and Dr. Jakobovits' son is the beneficiary. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $16.41 to $17.38. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $16.41 to $17.21. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $14.00 to $14.26. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $14.00 to $14.26. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request. Shares held in a revocable trust of which Dr. Jakobovits and her spouse are co-trustees. /s/ Nick Harvey, Attorney-in-Fact for Aya Jakobovits 2022-02-14