/api/v1/cusip/cik/{cik}

Look up company CUSIP mappings by CIK number.

Look up company CUSIP mappings by CIK number. Supports both short (e.g. 320193) and 10-digit zero-padded CIK formats.

Why use this

Reverse lookup from SEC CIK to CUSIP and ticker — when your input is the SEC's canonical company identifier (e.g. you parsed a filing accession and want the CUSIP for downstream 13F holdings query). Returns ALL CUSIPs registered to the issuer, not just the primary — multi-class issuers like BRK (A + B classes), GOOGL (Alphabet A + C), and FTCH (with foreign-equivalent classes) can have 2-5 CUSIPs per CIK. Pair with [GET /api/v1/cusip/cusip6/{cusip6}](/docs/reference-data/cusip-api/get-cusip-cusip6) when you also want preferred / convertible / debt securities for the same issuer.

Common use case

Filing-parsing pipelines that emit `(cik, accession_number)` rows and need to enrich with `(cusip, ticker)` for downstream holdings reconciliation. Also useful in 'show me all share classes for this issuer' workflows — Berkshire Hathaway CIK `0001067983` returns both BRK-A (`084670108`) and BRK-B (`084670702`) in one call.

Reverse direction of the issuer lookup — given an SEC CIK, return all registered CUSIPs and their ticker/security_group classifications. The natural bridge from filing-parser output (which emits CIK-keyed accession rows) into CUSIP-shaped 13F holdings queries. Multi-class issuers return all classes — Berkshire 0001067983 returns both BRK-A (084670108) and BRK-B (084670702); Alphabet 0001652044 returns GOOGL (02079K305) and GOOG (02079K107). For preferred / convertible / debt sibling securities use GET /api/v1/cusip/cusip6/{cusip6} which queries by issuer prefix instead. CIK normalization is permissive: both 0000320193 and 320193 resolve to the same canonical 10-char form via SQL ltrim(cik, '0') — the v3.14.2 ticker-shim equivalent for CIKs.

Parameters

Name	In	Required	Default	Allowed	Description	Example
cik	path	required	—	—	SEC CIK number. Both formats accepted: 10-character zero-padded (`0000320193`) and short unpadded (`320193`). Server-side normalization handles both via `func.ltrim(cik, '0')` matching. Returns 404 when no CUSIP is registered to the CIK (rare; typically foreign-private issuers without ADR programs, or pre-registration shell companies).	0000320193

Response schema

Field	Type	Nullable	Description
cik	string	no	Echoed CIK in 10-character zero-padded form regardless of input format.
issuer_name	string	no	Issuer legal name from the canonical catalog (all-caps EDGAR convention).
securities	array	no	Array of all CUSIPs registered to this CIK — one entry per security class (common stock, preferred, convertible, etc.). Multi-class issuers like BRK (2 classes) or AMZN-pre-split (1 class) return correspondingly-sized arrays. Order is by `security_group` priority then by ticker alphabetical (Stocks > Preferred > Warrants > Debt > Other) so common-equity classes appear first.
securities[].cusip	string	no	9-character CUSIP for this security class.
securities[].ticker	string	yes	Canonical hyphen-form ticker. Null for unmapped tickers (debt securities, private placements).
securities[].security_group	string	yes	Security classification — `Stocks` / `ETFs` / `Preferred` / `Warrants` / `Debt` / `Other`. Useful for filtering to common-equity-only or all-equity-classes views.
securities[].cusip6	string	no	6-character CUSIP issuer prefix. All securities for one CIK typically share the same CUSIP6 (Berkshire's BRK-A and BRK-B both share `084670`), but corporate-action successors can have different CUSIP6 prefixes (RKLB has CUSIP6 history `G9442R` -> `773122` -> `773121`).

Sample response

"cik": "0001067983"
"issuer_name": "BERKSHIRE HATHAWAY INC"
"securities":
]

}

Errors

Status	Label	Description
200	OK	Request succeeded.
400	Bad Request	Invalid query, body, or path parameter.
401	Unauthorized	Missing or invalid Authorization header / api_Token.
402	Payment Required	Insufficient token balance for this call. Top up
429	Too Many Requests	Rate limit exceeded for your tier (see /pricing for tier limits). Tier limits
500	Server Error	Unexpected server-side failure. Retry with backoff; report if persistent.

Code samples

Reveal credentials

curl "https://api.finradar.ai/api/v1/cusip/cik/{cik}?api_Token=YOUR_API_KEY" \
  -H "Authorization: Bearer YOUR_JWT_TOKEN"

Generate an API key in /account/credentials to run live queries (literal YOUR_API_KEY placeholder shown until then).