Merck & Co.vs.Zoetis
MRK vs ZTS · both in Big pharma, part of the Medicine, pharma & life science value chain: Large, diversified pharmaceutical groups with broad portfolios across therapeutic areas.
Merck & Co. is about 9.3× larger than Zoetis by market cap; Zoetis trades at the lower P/E (12.4 vs 34.1); year to date, Merck & Co. leads (+17.4% vs −39.9%).
Side by side
| MRK | ZTS | |
|---|---|---|
| Market cap | $305B | $32.9B |
| Price | $123.54 | $75.56 |
| Today | −1.2% | +0.6% |
| Return YTD | +17.4% | −39.9% |
| Return 1Y | +47.0% | −52.4% |
| P/E | 34.1 | 12.4 |
| P/S | 4.6 | 3.5 |
| P/B | 6.7 | 10.2 |
Data as of 2026-07-11 · updates daily after U.S. close
The two companies
Merck & Co.MRK
American pharmaceutical group with strengths in oncology (Keytruda), vaccines and animal health.
Full MRK profile →ZoetisZTS
The world’s largest animal health company — medicines and vaccines for pets and livestock, spun off from Pfizer in 2013.
Full ZTS profile →More comparisons in Big pharma
See where MRK and ZTS sit in the full Medicine, pharma & life science map — every segment from suppliers to end markets.Open the Life science value chain →