Prime Medicine, Inc.

Item 1. Legal Proceedings

We were engaged in binding arbitration proceedings with Beam regarding the Beam Collaboration Agreement. A dispute arose between the parties following our March 18, 2025 announcement that we are developing a Prime Editing-based treatment for AATD. On April 16, 2025, Beam filed an arbitration demand with the AAA, alleging that we breached the Beam Collaboration Agreement by developing a product for the treatment of AATD and by allegedly not complying with certain obligations to transfer technical information to Beam pursuant to the Beam Collaboration Agreement. Beam also made related claims for trade secret misappropriation and various business torts based on similar allegations. Beam sought both declaratory, injunctive, and monetary relief. On April 18, 2025, we filed an arbitration demand with the AAA seeking a declaration that our AATD program is within our “Field” as defined by the Beam Collaboration Agreement. The arbitrations were consolidated and a hearing was conducted earlier this year.

On July 6, 2026, we received a final award, or the Final Award, from the arbitration tribunal, or the Tribunal. In the Final Award, the Tribunal declared that PM647, our development candidate for the treatment of AATD, is within our "Field," and that we therefore did not breach the Beam Collaboration Agreement. Consequently, the Tribunal denied Beam's requests for damages and injunctive relief based on Beam's assertion that we breached the Beam Collaboration Agreement. The Tribunal denied the remaining claims brought by Beam and us.