Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced that the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended ("HSR"), in connection with Merck's pending acquisition of Terns Pharmaceuticals, Inc. ("Terns") (NASDAQ:TERN) expired at 11:59 p.m., Eastern Time, on April 23, 2026.