When did MRK join the S&P 500?

Merck & Co. joined the S&P 500 index on 1957-03-04.

What sector is MRK in?

MRK is in the Health Care sector, Pharmaceuticals industry.

MRK — Merck & Co.

Name: MRK Institutional Holdings (13F) — 2026Q1
Creator: SEC EDGAR
License: https://www.sec.gov/data

Pharmaceuticals · Health Care

S&P 500 Timeline

1957-03-04Joined S&P 500

Merck & Co., Inc. is a healthcare company that provides health solutions through its prescription medicines, vaccines, biologic therapies, animal health, and consumer care products. It operates through the following segments: Pharmaceuticals, Animal Health, and Other. The Pharmaceuticals segment includes human health pharmaceutical medicines and vaccine products. The Animal Health segment discovers, develops, manufactures, and sells animal health products, such as pharmaceutical and vaccine products, for the prevention, treatment, and control of diseases in livestock and companion animal species. The Other segment includes sales from non-reportable portions of healthcare services.

Key Facts

Status	Active
Sector	Health Care
Industry	Pharmaceuticals
Joined	1957-03-04
Tenure	69 yrs

Industry Peers

BMY JNJ LLY PFE VTRS ZTS

Sector Peers

A ABBV ABT ALGN AMGN BAX BDX BIIB BMY BSX

Institutional Holdings (13F)

3,771 institutions hold MRK, totaling 2.60B shares ($290.6B) · As of 2026Q1

Rank	Institution	Shares	Value
1	VANGUARD CAPITAL MANAGEMENT LLC	322.0M	$38.7B
2	BlackRock, Inc.	225.8M	$27.2B
3	STATE STREET CORP	119.3M	$14.5B
4	MORGAN STANLEY	137.2M	$14.2B
5	DZ BANK AG Deutsche Zentral Genossenschafts Bank, Frankfurt am Main	133.8M	$14.0B
6	WELLINGTON MANAGEMENT GROUP LLP	84.3M	$10.1B
7	BARCLAYS PLC	88.1M	$9.7B
8	VANGUARD PORTFOLIO MANAGEMENT LLC	67.3M	$8.1B
9	GEODE CAPITAL MANAGEMENT, LLC	59.6M	$7.1B
10	Employees Provident Fund Board	97.7M	$6.7B

View all holders →

Data source: Wikipedia · CC BY-SA 4.0 · SEC EDGAR 13F · Updated 2026-07-10