Does The Move In Merck Stock Change Anything?

Merck (MRK) stock returned 69.6% over the year to October 8, 2026, against 16.3% for the S&P 500. The gain built up over a year of drug approvals and clinical trial results, arriving just as the company prepares for the patent loss on Keytruda, its top-selling drug. So what did Merck show investors over those twelve months.