X0508 4 2025-11-25 0001527753 Personalis, Inc. PSNL 0001401786 Tachibana Aaron C/O PERSONALIS, INC. 6600 DUMBARTON CIRCLE FREMONT CA 94555 false true false false CFO AND COO 1 Common Stock 2025-11-25 4 M 0 103668 9.16 A 268126 D Common Stock 2025-11-25 4 S 0 103668 10.78 D 164458 D Stock Option (right to buy) 9.16 2025-11-25 4 M 0 103668 0 D 2029-03-13 Common Stock 103668 108832 D The sales and option exercise reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on August 7, 2025. The price reported above reflects the weighted average price of the shares sold. The sale price ranged from $10.25 to $11.10 per share. Upon request from the SEC staff, the Issuer, or a security holder of the Issuer, the Reporting Person will provide full information regarding the number of shares sold at each separate price within the range set forth in this Form 4. The shares subject to the option are fully vested and exercisable. /s/ Aaron Tachibana 2025-11-28