Public Trademark API

Endpoint

GET /api/trademarks/{serialNumber}

{serialNumber} must be an 8-digit USPTO serial. No API key is required for individual lookups. Responses are publicly cacheable and include CORS headers for browser clients.

Rate limits: 1 request per 10 seconds and 30 requests per hour per IP address. Exceeding either limit returns HTTP 429 with a Retry-After header. Cloudflare-verified search and AI crawlers are exempt. HTML record pages and markdown via Accept: text/markdown are not rate limited.

curl -sS https://getcopymark.com/api/trademarks/87654321

Response fields

• Mark name, serial, and registration number
• Status code with plain-English explanation when catalogued
• Filing, status, and registration dates
• Owners, Nice classes, and goods/services
• Prosecution events with plain-English notes when available
• Office Action issues, deadlines, and document URLs when enriched
• pageUrl — the canonical CopyMark HTML page
• tsdrUrl — the official USPTO TSDR record

OpenAPI

Machine-readable specification: https://getcopymark.com/openapi.json

HTML records

Every serial also has a crawlable HTML page at https://getcopymark.com/trademark/{serialNumber}. Prefer the HTML page for search indexing; use the JSON API for programmatic lookups.

Browse trademark indexes

AI agents

AI agents may freely read and cite getcopymark.com. Send Accept: text/markdown on any public HTML page for markdown, or use the JSON API above. See For AI agents for citation rules and discovery URLs.