Merck EVP David Michael Williams' Stock Transactions and Restricted Stock Unit Vesting

This Form 4 filing reports transactions by David Michael Williams, Executive Vice President and Chief Information & Digital Officer of Merck & Co., Inc. On April 29, 2026, Williams received 1,377 shares of Merck common stock through the vesting of restricted stock units (RSUs) at $0 cost. Concurrently, he acquired 1,377 shares at $110.03 per share and disposed of 679 shares at the same $110.03 price. Following these transactions, Williams holds 31,716 shares of Merck common stock directly and 2,755 RSUs that will continue vesting in equal installments on April 29, 2027 and 2028. The RSUs represent contingent rights to receive Merck common stock, with the first installment vesting on the reported date. These transactions reflect typical executive compensation activities including equity award vesting and related stock transactions.