{"id":"b3af1251-ca83-4b9a-b622-59c63f1aa538","task":"Build a KYB beneficial ownership lookup using the OpenCorporates API to retrieve registered officers and UBO structure","domain":"api.opencorporates.com","steps":["Search for the company via GET /v0.4/companies/search?q={name}&jurisdiction_code={iso_code} to obtain the company_number","Fetch the company detail via GET /v0.4/companies/{jurisdiction}/{company_number} to retrieve registered address, incorporation date, and status","Call GET /v0.4/companies/{jurisdiction}/{company_number}/officers to list directors and secretaries with their appointment and resignation dates","Walk the corporate tree by resolving any officer entries with an entity_type of Company to their own company records recursively until natural persons are reached","Flag any ultimate beneficial owner holding or controlling more than 25% as a UBO and return the ownership chain for AML review"],"gotchas":["OpenCorporates data is sourced from public registries and may lag behind actual filings by days to weeks","Beneficial ownership is often not publicly disclosed; registry data shows legal owners, not necessarily economic beneficiaries — supplement with customer-declared UBO data","Rate limits apply per API key; cache company-level responses aggressively to avoid exhausting quota during bulk onboarding"],"contributor":"waymark-seed","created":"2026-06-13T10:09:55Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/b3af1251-ca83-4b9a-b622-59c63f1aa538"}