Merck vs Pfizer (MRK vs PFE)
Side by side from their SEC filings: revenue, margins, growth, returns and valuation, plus short interest, insider activity and institutional ownership.
Merck is the larger company by revenue ($65.0B vs $62.6B) and market value ($306.3B vs $139.5B). Merck has grown revenue faster over the last 4 fiscal years (+33.5% cumulative vs -23.0%). Pfizer trades at the lower trailing P/E (18.7x vs 34.9x).
About Merck
Merck & Co., Inc. is a pharmaceutical company that develops and sells prescription medicines, vaccines, and animal health products. It serves healthcare providers, patients, and animal health customers worldwide. The company also collaborates with other firms to develop and commercialize various pharmaceutical products.
About Pfizer
Pfizer Inc. is a global biopharmaceutical company that discovers, develops, manufactures, markets, sells, and distributes medicines and vaccines worldwide. Its main products include treatments in oncology, internal medicine, vaccines, inflammation, and immunology, serving healthcare providers and patients across developed and emerging markets. Pfizer operates through its Biopharma segment, which manages commercial operations and product portfolios such as primary care, specialty care, oncology, and hospital and biosimilars.
Head to head (MRK FY2025 vs PFE FY2025)
| Metric | MRKFY2025 | PFEFY2025 |
|---|---|---|
| Revenue | $65.01B | $62.58B |
| Revenue growth (YoY) | 1.3% | -1.6% |
| Gross margin | 74.8% | 74.3% |
| Operating margin | — | — |
| Net margin | 28.1% | 12.4% |
| Net income | $18.25B | $7.77B |
| Diluted EPS | $7.28 | $1.36 |
| FCF margin | 19.0% | 14.5% |
| ROE | 34.7% | 9.0% |
| Debt / equity | 0.9× | 0.7× |
| Market cap | $306.33B | $139.52B |
| P/E (TTM) | 34.9× | 18.7× |
Fundamentals are from each company’s SEC filings (MRK FY2025, PFE FY2025). P/E and market cap are derived from recent market prices and update daily.
Five-year trend (as reported)
| Revenue | FY2021 | FY2022 | FY2023 | FY2024 | FY2025 |
|---|---|---|---|---|---|
| MRK | $48.70B | $59.28B | $60.12B | $64.17B | $65.01B |
| PFE | $81.29B | $91.79B | $59.55B | $63.63B | $62.58B |
Peer standing
Where each company ranks among the 198 pharmaceutical companies, on the same scale. Each figure is ranked only against peers that report it. Percentiles describe position in the distribution, not a rating.
| Metric | MRK | PFE |
|---|---|---|
| Gross margin | 74.8%67th percentile of 68 | 74.3%64th percentile of 68 |
| Net margin | 28.1%82nd percentile of 121 | 12.4%72nd percentile of 121 |
| FCF margin | 19.0%77th percentile of 109 | 14.5%67th percentile of 109 |
| Revenue growth (YoY) | +1.3%36th percentile of 186 | -1.6%30th percentile of 186 |
| ROE | 34.7%91st percentile of 167 | 9.0%73rd percentile of 167 |
| P/E (TTM) | 34.9×77th percentile of 61 | 18.7×57th percentile of 61 |
| Debt / equity | 0.89×77th percentile of 65 | 0.71×59th percentile of 65 |
| Short interest (days to cover) | 2.30d21st percentile of 197 | 2.69d27th percentile of 197 |
Short interest
| FINRA settlement data | MRK | PFE |
|---|---|---|
| Shares sold short | 31.4M | 163.6M |
| Change vs prior settlement | +3.7% | +0.9% |
| Days to cover | 2.30 | 2.69 |
| As of settlement | 2026-06-30 | 2026-06-30 |
Source: FINRA Consolidated Short Interest. FINRA is the owner and source of the FINRA-supplied data; republishing or redistributing it is not permitted. Not presented as a percentage of float. No FINRA endorsement of this product is implied.
Insider activity (last 90 days)
| Form 4 open-market activity | MRK | PFE |
|---|---|---|
| Buys | — | 0 |
| Sells | — | 1 ($51,400) |
Open-market purchases and sales reported on SEC Form 4 (grants, exercises and tax withholding excluded). For context, about 16% of covered companies saw any open-market insider buy in a 90-day window.
Held by the same investors
8 tracked 13F managers hold both Merck and Pfizer as of their latest quarterly filings: AQR Capital Management, Citadel Advisors, D. E. Shaw, Dodge & Cox, Gotham Asset Management, Millennium Management, Point72 Asset Management, Two Sigma Investments. See which superinvestors hold your own portfolio with the smart money checker.
Go deeper
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Data sourced from SEC EDGAR (public domain). Figures are as-reported and may be unaudited or restated; verify against the source filings before relying on them. Comparisons are descriptive (higher or lower on a reported figure), not a rating or a recommendation. Informational only. Not investment advice.