Material Event (Form 8-K)

Item 8.01 Other Events.

On May 19, 2026, Cardiff Oncology, Inc. (the "Company") filed a lawsuit against Nerviano Medical Sciences S.r.L ("NMS") disputing NMS's allegation that the Company materially breached its license agreement (Agreement) for onvansertib. The complaint, filed in the United States District Court for the Southern District of California, seeks injunctive relief requiring NMS to continue performing under the Agreement and a declaratory judgment that Cardiff did not breach the Agreement.

As previously disclosed on February 24, 2026, the Company received a written notice from NMS alleging that the Company is in material breach of the Agreement because the Company did not name an NMS employee as a joint inventor on the Company's U.S. Patent Nos. 12,144,813 and 12,263,173 (the "Cardiff Patents") and did not agree to file a joint invention continuation patent application. The Company maintains there was no breach and that the Agreement does not require the Company to name NMS employees on inventions made exclusively by the Company, or to make what the Company believes are false or inaccurate representations regarding inventorship to the U.S. Patent and Trademark Office. While Cardiff had engaged in discussions with NMS, the Company believes that judicial intervention is needed.

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