SEC CENTRAL INDEX KEY

Merck & Co., Inc. CIK Number

The SEC Central Index Key (CIK) for Merck & Co., Inc. (MRK).

CIK (CENTRAL INDEX KEY)
0000310158
Also written as 310158 (without leading zeros).
Company
Merck & Co., Inc.
Ticker
MRK
Download MRK filings (PDF) →View on SEC EDGAR

What is a CIK number?

A CIK (Central Index Key) is the unique, permanent identifier the U.S. Securities and Exchange Commission assigns to every filer — companies, funds, and individuals — in its EDGAR system. Unlike a stock ticker, a CIK never changes: even if Merck & Co., Inc. changed its ticker or name, its CIK (0000310158) would stay the same.

That stability is why the CIK is the most reliable way to pull a company's filings programmatically. Every 10-K, 10-Q, 8-K, and Form 4 for Merck & Co., Inc. is indexed under CIK 0000310158.

CIK vs ticker — what is the difference?

  • Ticker (MRK) — exchange trading symbol; can change or be reused.
  • CIK (0000310158) — SEC filer ID; permanent, one per filer, used across all EDGAR filings.
  • Leading zeros are optional: 0000310158 and 310158 refer to the same filer.

How to use Merck & Co., Inc.'s CIK

Paste CIK 0000310158 into EDGAR full-text search to see every filing, or skip the friction and download MRK filings as clean PDFs here. To look up any other company's CIK, use the CIK lookup directory.

Source: SEC EDGAR company index (sec.gov). CIK data is public.