"error" key with machine-readable fields for programmatic handling.
Error Response Structure
Error Catalog
entity_too_large carries an error.reason discriminator so you can branch without parsing the message: member_owners_too_large means the entity or group resolved to more member owners than the cap (the error also carries member_count and member_count_limit), and family_graph_too_large means the GLEIF family-graph walk exceeded its node or depth bound before owners were counted, which only fires on ?entity_group= (the error carries related_entity_limit and depth_limit). Either way, narrow the query with additional filters, query a specific member directly, or use ?entity_id= for a single entity instead of ?entity_group=; the caps bound fan-out cost and are not retryable as-is.
Handling Errors
Errors return non-2xx status codes. The response body always contains a structurederror object and a top-level request_id.
instanceof patterns and automatic retries.
Reporting a persistent server error
Server faults (500 internal_error, 502 upstream_error, 503 service_unavailable, 504 timeout) carry a suggestion that points you at the feedback channel. If retrying with backoff does not clear the error, submit it to POST /v1/feedback with the response’s request_id. Signa snapshots the matching request log onto the report, so the team can investigate exactly what you hit. Client errors (4xx) never carry this hint, they are fixed on your side by correcting the request. See Submit Feedback for the full flow.
Idempotency and 409 Conflict
Mutating requests (PATCH, DELETE, and non-exempt POST) require an Idempotency-Key header (1-255 characters of [A-Za-z0-9_-]):
Idempotent-Replayed: true response header and preserve the
original request_id.
Same key + different body = 409 conflict error.
Same key while the first request is still in flight = 409 idempotency_processing: wait for the original to finish, then retry.
Idempotency keys are scoped to your organization and expire after 24 hours.
Only successful (2xx) responses are cached, so a failed request never pins you
to its error.
POST /v1/trademarks(search)POST /v1/trademarks/batch(batch lookup)POST /v1/suggest(and other suggest endpoints)POST /v1/watches/preview(dry-run match count)POST /v1/alerts/lookup(bulk read by IDs)
[A-Za-z0-9_-]); a malformed value returns 400 even there.
POST /v1/organization/api-keys and POST /v1/organization/api-keys/{id}/rotate are not exempt. Replay is the
correct semantic for endpoints that mint one-time secrets: retrying the
same Idempotency-Key returns the same secret instead of minting a
second credential.Troubleshooting by Symptom
I'm getting 401 on every request
I'm getting 401 on every request
Check your Authorization header format. It must be
Authorization: Bearer sig_YOUR_KEY (with the Bearer prefix). Common mistakes:- Missing
Bearerprefix:Authorization: sig_YOUR_KEY - Wrong key prefix: only keys of the form
sig_{48 hex chars}are accepted. Any other prefix is rejected with 401 before any database lookup. - Expired key: check
expires_aton your API key - Revoked key: check the API key status in your dashboard
I'm getting 403 'insufficient scope'
I'm getting 403 'insufficient scope'
Your API key is valid but does not have the required scope for this endpoint. Each endpoint requires specific scopes:
- Trademark search, list, and entity GET endpoints need
trademarks:read - The event feed (
/v1/events) needsevents:read - Watches, alerts, webhooks, portfolios, and saved searches need
portfolios:manage - API key management needs
api-keys:manage - Usage, plan, and log endpoints need
billing:read
I'm getting 400 'validation_error' but my request looks correct
I'm getting 400 'validation_error' but my request looks correct
Common causes:
- Missing required filter:
GET /v1/trademarksrequires at least one filter (no unscoped list queries). - Wrong date format: Use ISO 8601 (
2026-03-24or2026-03-24T12:00:00Z). - Array syntax: Bracketed keys (e.g.
offices[]=uspto) are not accepted; repeated keys (e.g.offices=uspto&offices=euipo) are accepted as a fallback, but the canonical form is comma-separated (offices=uspto,euipo). - Date range syntax: Use flat underscore operators, not brackets:
?filing_date_gte=2020-01-01&filing_date_lt=2025-01-01. - Boolean values: Only the literal strings
trueandfalseare accepted.1,0,yes,no, andTRUEall return a validation error. - application_number without office: When filtering by
application_numberorregistration_number, you must also specifyoffice. - Missing Idempotency-Key: Mutating requests (
PATCH,DELETE, and non-exemptPOSTs) require this header. Read-shaped POSTs (search, batch, suggest, watch preview, alert lookup) do not.
I'm getting 410 'entity_merged' for an owner I used yesterday
I'm getting 410 'entity_merged' for an owner I used yesterday
Entity resolution runs periodically. When two owner records are identified as the same entity, one is merged into the other. The
410 response includes a merged_into field pointing to the canonical record.Update your cached ID to the new one. All trademarks previously associated with the old owner are now under the canonical record.Resolved entities (ent_*) can also 410. When two resolved entities are fused, the loser’s ent_ id returns 410 entity_merged with the successor in merged_into: follow that field to the canonical record. An entity id for an owner that has since been linked to a company profile does not 410; it transparently resolves to the real entity (the returned id may differ from the one you requested).Search returns different results than the detail endpoint
Search returns different results than the detail endpoint
This is expected behavior due to the eventual consistency model. Search results are eventually consistent (typically under 30 seconds lag after a write), while detail endpoints are immediately consistent.If you just updated a record, wait a few seconds and retry the search. For time-sensitive workflows, use the detail endpoint as the source of truth.
I'm hitting rate limits during bulk operations
I'm hitting rate limits during bulk operations
For bulk lookups, use Batch Get Trademarks (up to 100 IDs per request) instead of individual GET requests. This counts as one request against your rate limit.For search-heavy workloads, consider caching results on your side, using cursor pagination instead of re-executing searches, or upgrading your plan.
I'm getting 503 errors intermittently
I'm getting 503 errors intermittently
This indicates a transient backend issue. The error is retryable: wait for the
retry_after period and retry with exponential backoff. If 503 errors persist for more than a few minutes, email support@signa.so with a request_id from one of the failed calls.