EXHIBIT 99.1
JOINT FILING AGREEMENT
We, the undersigned, hereby express our agreement that the attached Schedule 13D (or any amendments thereto) relating to the common stock of Personalis, Inc. on behalf of each of us.
Dated: June 10, 2026
Lightspeed Venture Partners Select, L.P. By: Lightspeed General Partner Select, L.P. Its General Partner By: Lightspeed Ultimate General Partner Select, Ltd. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director Lightspeed General Partner Select, L.P. By: Lightspeed Ultimate General Partner Select, Ltd. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director Lightspeed Ultimate General Partner Select, Ltd. By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director Lightspeed Venture Partners VIII, L.P. By: Lightspeed General Partner VIII, L.P. Its General Partner By: Lightspeed Ultimate General Partner VIII, Ltd. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director LSVP VIII Trust By: Lightspeed Trustee VIII, LLC its Trustee By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Member | Lightspeed Venture Partners Select IV, L.P. By: Lightspeed General Partner Select IV, L.P. Its General Partner By: Lightspeed Ultimate General Partner Select IV, L.L.C. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Managing Member Lightspeed General Partner Select IV, L.P. By: Lightspeed Ultimate General Partner Select IV, L.L.C. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Managing Member Lightspeed Ultimate General Partner Select IV, L.L.C. By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Managing Member Lightspeed General Partner VIII, L.P. By: Lightspeed Ultimate General Partner VIII, Ltd. Its General Partner By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director Lightspeed Ultimate General Partner VIII, Ltd. By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Director Lightspeed Trustee VIII, LLC By: /s/ Ravi Mhatre Name: Ravi Mhatre Title: Member |