# Merck & Co., Inc. (MRK)

> Merck makes prescription medicines and vaccines for people, and medicines, vaccines and monitoring products for animals.

- Exchange: NYSE · Sector: Healthcare · Industry: Drug Manufacturers General
- Headquarters: Rahway, New Jersey, United States
- Founded: 1891
- SEC CIK: 0000310158 ([filings on EDGAR](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=0000310158))
- Full page: https://inspectstocks.com/stocks/mrk
- Data as of: price 2026-09-28; newest filing used 2026-08-07; latest fiscal period ended 2026-06-30

## Grade

**A** on the growth-and-cash rubric, 5 of 5 checks passed.

| Check | Result | Now | Before |
| --- | --- | --- | --- |
| Revenue growing overall | passed | $66.6B | $58.3B |
| Revenue growing recently | passed | $66.6B | $65B |
| Free cash flow positive | passed | $16.1B |  |
| Free cash flow growing overall | passed | $16.1B | $10.8B |
| Free cash flow growing recently | passed | $16.1B | $12.4B |

Business quality (the + / − mark): 3 of 5 checks passed.

| Check | Result | Now | Before |
| --- | --- | --- | --- |
| Profitable | passed | 4.8% |  |
| Healthy profit margin | failed | 4.8% |  |
| Good return on equity | failed | 6.0% |  |
| Debt under control | passed | 0.96 |  |
| Turns sales into cash | passed | 24.1% |  |

How the grade works: the letter counts failed checks (none → A, one → B, two → C, three → D, four or more → F). It is built from SEC filings only — the share price never enters it — and describes the business, not whether the stock is worth buying.

## Key figures

In US dollars, as filed.

| Measure | Value |
| --- | --- |
| Revenue, trailing twelve months | $66.6B |
| Net income, trailing twelve months | $3.2B |
| Free cash flow, trailing twelve months | $16.1B |
| Net margin | 4.8% |
| Return on equity | 6.0% |
| Debt to equity | 0.96 |
| Diluted EPS, trailing twelve months | $1.26 |
| Share price | $148.70 |
| Market value | $366.9B |
| Price / earnings | 118.0x |
| Price / sales | 5.5x |

## What the business does

Merck discovers, develops, manufactures and sells prescription medicines and vaccines for people, including cancer treatments such as Keytruda and vaccines such as Gardasil. Its Animal Health business sells medicines, vaccines and animal identification and monitoring products to veterinarians, farmers and other animal-care businesses.

### How it makes money

- **Human medicines and vaccines (Pharmaceutical segment)** (90.1% (FY2025)) — Merck primarily sells prescription medicines to wholesalers, retailers, hospitals, government agencies and health-care organizations. It sells vaccines mainly to physicians, wholesalers, distributors and government entities. For some partnered products, it records royalties or its share of product profits.
- **Animal medicines, vaccines and related products (Animal Health segment)** (9.9% (FY2025)) — Merck sells veterinary medicines, vaccines and animal identification, tracking and monitoring products to veterinarians, distributors, animal producers, farmers and pet owners.

### Products

- **Keytruda and Keytruda Qlex** — Cancer medicines. Keytruda is given into a vein; Keytruda Qlex is a form given as an injection under the skin.
- **Gardasil and Gardasil 9** — Vaccines that help prevent certain cancers and other diseases caused by some types of human papillomavirus.
- **Januvia and Janumet** — Prescription medicines used to help lower blood sugar in adults with type 2 diabetes.
- **Winrevair** — A medicine for adults with pulmonary arterial hypertension, a disease that raises blood pressure in the arteries from the heart to the lungs.
- **Lipfendra** — An oral medicine used with diet and exercise to lower low-density lipoprotein cholesterol in adults with high cholesterol.
- **Bravecto** — A range of medicines that protect dogs and cats against fleas and ticks, including oral, topical and injectable forms.

### Customers

- Drug wholesalers and retailers buy Merck's human prescription medicines for distribution to pharmacies and other care providers.
- Hospitals, government agencies and managed health-care organizations buy or arrange access to prescription medicines.
- Physicians, wholesalers, distributors and government entities buy or distribute Merck's human vaccines.
- Veterinarians, animal-health distributors, animal producers and farmers buy veterinary medicines, vaccines and animal monitoring products.
- Pet owners buy Merck's companion-animal products, sometimes through veterinary practices or distributors.

### Competitors

- Pfizer Inc. (PFE) — Human prescription medicines, cancer treatments and vaccines.
- Bristol Myers Squibb Company (BMY) — Human prescription medicines, including cancer treatments.
- AstraZeneca PLC (AZN) — Human prescription medicines, including cancer treatments.
- GSK plc (GSK) — Human prescription medicines and vaccines.
- Eli Lilly and Company (LLY) — Human prescription medicines, including diabetes and other medicines.
- Zoetis Inc. (ZTS) — Veterinary medicines and vaccines for pets and livestock.

### What it depends on

- Sales depend heavily on a small number of major medicines. Keytruda was Merck's biggest-selling product in 2025, and sales depend on continued demand, market access and patent protection.
- Merck depends on patents and other legal protections for medicines. When products lose market exclusivity, generic or biosimilar versions can take sales; the 2026 quarterly report describes this pressure on Januvia, Janumet and Bridion.
- Sales depend on regulatory approval, health-care coverage and government and insurer purchasing decisions. The company also reports that certain raw or intermediate materials come primarily from a single supplier.
- Gardasil sales in China depend on demand and the relationship with its Chinese distributor and commercialization partner; Merck suspended shipments in 2025 and resumed limited shipments in 2026.

### What could go wrong

- Merck identifies its dependence on patent rights as a risk: if patents are invalidated or products lose market exclusivity, generic or biosimilar competition can rapidly reduce sales. Keytruda is its biggest-selling product, and the company reports that U.S. government price-setting for certain medicines is also affecting its business.
- Government and private health-care cost controls can lower prices or restrict access. The latest quarterly report describes price-setting, Medicaid discounts and other cost-reduction measures, including a German health-care reform law expected to put downward pressure on sales there.
- Vaccine sales can be affected by changes in vaccination recommendations, government purchasing and demand. Gardasil sales fell in China, where Merck suspended shipments before agreeing to limited shipments under a revised distributor contract; U.S. childhood immunization schedule changes were also subject to a court injunction and government appeal.

## More on this company

- [Overview](https://inspectstocks.com/stocks/mrk)
- [Financial statements](https://inspectstocks.com/stocks/mrk/financials)
- [Competitors](https://inspectstocks.com/stocks/mrk/peers)
- [Earnings](https://inspectstocks.com/stocks/mrk/earnings)

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Source: InspectStocks, built from the company’s own SEC filings. This describes a business — it is not investment advice and not a recommendation to buy or sell anything.