Holders

GET /v1/companies/{id}/holders

Form 13F turned around: given a company, the managers that reported holding it, for one report period. Sorted by value_usd, largest first. Every row carries its source accession.

curl -H "X-API-Key: $BELFORT_API_KEY" \
  "https://belfort-data-api.vercel.app/v1/companies/AAPL/holders?limit=25"

Parameters

Parameter	Values	Default
period	A report period end, YYYY-MM-DD.	The newest period on file
limit	1–100 rows per page.	25
cursor	The previous page’s meta.next_cursor. Paging stays on the same period.

One holder

Field	Meaning
issuer_cik, period_end	The company held, and the report period.
manager_cik, manager_name	The manager that reported the holding.
accession, filed, is_amendment	The 13F filing, the day it was filed, and whether it’s an amendment.
cusip	The security, as filed.
map_method	How the CUSIP was linked to this company. See below.
value, value_unit, value_usd	The value as filed, its unit, and the value in dollars.
shares_or_principal, put_call	The position’s size, and whether it’s an option.

How a holding is linked to a company

A 13F lists securities by CUSIP and by the manager’s own spelling of the issuer’s name, never by the SEC company number. We link a CUSIP to a company only when two independent pieces of evidence agree:

• 13dg: a Schedule 13D or 13G filing states both the company’s CIK and the security’s CUSIP.
• issuer_prefix: the CUSIP’s issuer prefix was proven for exactly one company, and every name the SEC’s official list of 13(f) securities gives that CUSIP matches the company’s name.
• name_match: the official list’s issuer name matches exactly one company with no close rival, the company has a ticker, and every listed name for the CUSIP is covered by the company’s name history.

When the evidence doesn’t agree, the holding is left out rather than guessed. About 35% of 13F holding rows can’t be linked this way and aren’t served, so the holder list is incomplete. The measured check is on Quality.

What to expect

• Don’t add up filers that share a manager unless that relationship is stated. Related filers can report the same position.
• One period per answer. Ask for another with period.