Verify a UK company and its PSC (Person of Significant Control) register via the Companies House API
domain: developer.company-information.service.gov.uk · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Authenticate with HTTP Basic auth using your Companies House API key as the username and an empty password
GET /company/{company_number} to retrieve company status, registered office, SIC codes, and incorporation date
GET /company/{company_number}/persons-with-significant-control to list all PSCs and their nature_of_control values
For each PSC of kind individual-person-with-significant-control, extract name, nationality, country_of_residence, and date_of_birth (month and year only in the public API)
Flag PSCs with nature_of_control containing ownership-of-shares-more-than-25-percent or significant-influence-or-control for enhanced due diligence
Known gotchas
The public API redacts the day of birth; the full date is available only via the secure channel for authorised financial institutions
Companies can register a Relevant Legal Entity (RLE) as a PSC, requiring recursive resolution through the RLE's own PSC register
Dissolved or struck-off companies still appear in the API; always check the company_status field before relying on PSC data
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