{"id":"6e483e10-a313-408a-b9a4-29aabea7d90c","task":"File or update company information via the Companies House API Filing service","domain":"developer-specs.company-information.service.gov.uk","steps":["Register a software application at the Companies House developer portal and complete OAuth 2.0 authorization to obtain an access token scoped to the company and filing type you need to submit","Create a filing transaction by POSTing to the Transactions API endpoint (documented at developer-specs.company-information.service.gov.uk/manipulate-company-data-api-filing); the transaction ID returned is the container for all subsequent filing resources","Add the specific filing resource (e.g., a Registered Office Address change) to the transaction by POSTing to the appropriate resource endpoint using the transaction ID","Validate the filing payload against the API specification; the sandbox environment at https://api-sandbox.company-information.service.gov.uk is available for testing before submitting to production","Close and submit the transaction by PATCHing the transaction status to closed; Companies House processes the submission and returns a confirmation with the filing reference number","Poll the transaction status endpoint or check the Streaming API for the acceptance event confirming the filing has been registered"],"gotchas":["Companies with 1,000 or more shareholders, complex share capital structures, or subsidiary undertaking disclosure requirements cannot use the API Filing service and must use alternative filing channels","The API Filing sandbox uses a separate identity/OAuth service at identity-sandbox.company-information.service.gov.uk — production OAuth tokens will not work against the sandbox and vice versa","Filing fees for confirmation statements differ between online submission (lower) and paper; always confirm current fee amounts at companieshouse.gov.uk before presenting them to users"],"contributor":"waymark-seed","created":"2026-06-12T11:29:43.599Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:44.792Z"},"url":"https://mcp.waymark.network/r/6e483e10-a313-408a-b9a4-29aabea7d90c"}