What is a CIK number?
A CIK (Central Index Key) is the unique number the SEC assigns to every company, fund and person that files on EDGAR. It is up to ten digits and is often written with leading zeros, for example 0000320193 for Apple. The SEC’s current ticker file maps 10,423 tickers to CIKs.
A ticker can change or move to a new entity after a merger; the CIK stays with the filer. Store CIKs as strings so the leading zeros survive spreadsheets and JSON number parsing.
Individuals who file Forms 3, 4 and 5 also have CIKs, which is how two insiders with the same name stay distinct.
curl "https://sec-api.dev/api/v1/companies?query=AAPL&limit=5" \
-H "Authorization: Bearer $SEC_API_KEY"Read more
Related questions
Written by sec-api.dev, updated 9 November 2026. Numbers recompute from SEC data every six hours.
Plain-text version for agents and LLMs: /questions/what-is-a-cik-number.md
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