X0508 4 2023-12-04 0 0001726445 Seer, Inc. SEER 0001679971 Kogan Elona Esq. C/O SEER, INC. 3800 BRIDGE PARKWAY, SUITE 102 REDWOOD CITY CA 94065 0 1 0 0 Chief Legal Officer 0 Class A Common Stock 2023-12-04 4 S 0 8182 1.6951 D 162673 D The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs. Includes 1,168 shares and 3,100 shares acquired under the Issuer's 2020 Employee Stock Purchase Plan on May 15, 2023 and November 15, 2023, respectively. /s/ David Horn, by power of attorney 2023-12-06