Material Event (Form 8-K)

On June 9, 2025, IonQ, Inc. (the "Company") filed with the Securities and Exchange Commission (the "SEC") a prospectus supplement to the prospectus included in the Company's registration statement on Form S-3ASRfiled with the SEC on February 26, 2025 (File No. 333-285279)(the "Registration Statement"), covering the resale by certain selling stockholders of an aggregate of 903,195 shares of Company common stock, par value $0.0001 per share. The prospectus supplement was filed in accordance with a registration rights agreement in the form attached hereto as Exhibit 4.1. The foregoing description of the registration rights agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the form of the registration rights agreement, a copy of which is filed as Exhibit 4.1 hereto and is incorporated herein by reference. A copy of the legal opinion of Paul, Weiss, Rifkind, Wharton & Garrison LLP relating to the shares covered by the prospectus supplement is filed herewith as Exhibit 5.1, and is filed with reference to, and is hereby incorporated by reference into, the Registration Statement.