Company data API: the free and open routes

Every endpoint on this page was live-probed on 2026-07-29 by the Aidenix Atlas catalog.

What is a company data API?

A company data API is an endpoint that returns a structured record about a legal entity — name, status, address, identifiers, ownership — from the body that registered it, and 4 free routes cover most of the ground. In our data — the Aidenix Atlas catalog, every endpoint below live-probed on 2026-07-29 — those routes hold 8,631,371 US state incorporation records, 3,387,186 global LEI records, 10,432 SEC-registered issuers with tickers, and 5M+ UK companies. What separates them from a vendor product:

• The registrar publishes them, so the record is the legal fact rather than a copy of it.
• Three of the four need no key at all, and the fourth issues one free on registration.
• They answer existence, status, ownership and filings — not phone numbers or org charts.

Key facts at a glance

A key-facts table is the 60-second version of this page. In our data: 4 free routes, 3 of them keyless, 17 million records between them. Every row below comes from our own probe run of 2026-07-29, according to the Aidenix Atlas catalog logs:

Which company API answers which question?

A company API route is a single registrar's endpoint with its own identifier space, and picking the wrong one costs a day of joins that never resolve. Contract and counts checked in our probe run of 2026-07-29:

Which route you need follows from the question, not from the API that looks richest:

• If you are verifying that a US company legally exists → the state registry where it filed, one call, no key.
• If you are matching the same company across countries → GLEIF, because the LEI is the only free identifier that survives a border.
• If you need financial numbers → SEC EDGAR, and only for companies that file; private companies have no numbers to fetch anywhere at any price.
• If you need to know who is behind the shell → Companies House PSC, the only free beneficial-ownership register of this size.

How do you look up a company for free?

A free company lookup is one HTTP GET with a query parameter — no signup, no key, no client library. According to our probe of 2026-07-29, the GLEIF register answers name searches directly:

curl "https://api.gleif.org/api/v1/lei-records?filter%5Bentity.legalName%5D=Stripe,%20Inc.&page%5Bsize%5D=3"

We ran exactly that on 2026-07-29, and here are the top 3 results as returned, unedited:

Read what the sample teaches, because it is the whole discipline of registry work in three rows: a paint-industry company, a Belgian entity, and a holding company — and the operating payments business you were looking for is in none of them. Name search returns string matches, not companies. The status field matters as much as the name: LAPSED means the identifier stopped being maintained, so a record can look perfect and describe an entity nobody is filing for anymore.

Why do free company lookups return the wrong company?

Substring matching is the single most expensive failure in company data, and it is invisible until you read the output. We queried the New York state register for TESLA on 2026-07-29 across its 4,254,600 records; the first row it returned:

A film company called 10minu-TESLA-ter matched, because LIKE '%TESLA%' does not know where words end. In our data this pattern breaks naive pipelines more often than any authentication problem, and the fixes are mechanical:

• Anchor the match on word boundaries or exact equality, then widen only if nothing returns.
• Join on an identifier — CIK, LEI, state entity number — the moment you have one; never carry a name as the join key.
• Treat every name hit as a candidate to be confirmed against a second source, not as an answer.

What free company APIs cannot do

A free registry API is a lookup route with a hard ceiling, and in our data that ceiling has 4 walls. Of the nearly 4,000 sources the Aidenix Atlas catalog tracks, 0 free registry routes carry contact data, and our probe of 2026-07-29 found 1 of the 4 routes on this page partly down. Name the ceiling before you build on it:

• No contact data. No emails, no direct dials, no org charts — registrars do not collect them, so no free route has them.
• No private financials. A company that does not file with a securities regulator has no published numbers, and vendors that show them are estimating.
• No monitoring. These are lookup endpoints; detecting that a company changed status means re-polling it yourself.
• No guaranteed uptime. Our probe of 2026-07-29 found the Oregon state portal down at the DNS level for the third time this week — free means free, not operated for you.

Frequently asked questions

Is there a company API with no key at all? Yes — 3 of the 4 routes on this page are fully keyless: US state registries on Socrata, the GLEIF LEI register, and SEC EDGAR. SEC does require a declared User-Agent string with a contact address, and returns 403 without one, which reads as a block but is a courtesy rule.

How current is free company data? GLEIF publishes a golden copy daily — the file we probed on 2026-07-29 carried that same publish date. State registries update on their own filing cadence, typically daily to weekly, and SEC EDGAR appears within minutes of a filing being accepted.

Can I get company revenue from a free API? Only for filers. SEC XBRL returns real reported figures — a single companyfacts call for Apple came back with 503 distinct us-gaap metrics in our 2026-07-29 probe. For a private company, no free or paid source has audited numbers; what vendors sell is a model output.

How we verify these claims

Our verification method is a live probe, not a citation chain — every count and sample on this page comes from requests we sent ourselves on 2026-07-29. What the probe run covers, in our data:

• Endpoint liveness: each route was called for real, out of the nearly 4,000 sources the Aidenix Atlas catalog tracks.
• Live samples: the GLEIF and New York result tables are unedited API output, wrong matches included.
• Published failures: the Oregon outage above is in this page because it happened, not despite it.
• Freshness contract: when a source drifts, the probe fleet flags it and this page gets re-verified — the «last probed» date above is that promise.

Source facts from the Aidenix Atlas catalog, probed 2026-07-29. Found an error? The catalog re-probes on every report.