USPTO Trademark Search API What Developers and Founders Need to Know

A USPTO trademark search API lets you query the United States Patent and Trademark Office database programmatically, returning trademark data such as serial number, filing date, registration date, owner information, goods and services codes, and trademark status without visiting USPTO.gov manually. The official USPTO Open Data Portal exposes REST API endpoints for bulk retrieval and record lookup, while third-party trademark API services layer on features like phonetic matching, fuzzy search, and EU registry coverage. If you need a faster path to an automated trademark availability check, Startup Name Generator exposes an HTTP API and MCP server at /mcp that covers both USPTO and EUIPO with exact, phonetic, and fuzzy matching in a single call.

Updated September 2026

What a Trademark Search API Does

A trademark search API is an interface that lets software query a trademark database and retrieve structured results in formats like JSON, without a human manually operating a search engine. Instead of opening a browser and entering a wordmark into a portal, your application sends a query to an API endpoint and parses the response.

The United States Patent and Trademark Office maintains the USPTO trademark database, which covers all active trademarks, pending applications, and expired marks registered in the United States. Its Open Data Portal (USPTO Open Data Portal) publishes bulk datasets and REST API endpoints developers can use to extract USPTO trademark data, search by serial number, run a keyword search, filter by owner, international class, or services code, and check filing and expiration dates.

Third-party trademark API services build on top of that raw USPTO data to add features the official API does not offer natively, such as phonetic matching, fuzzy string comparison, EU trademark coverage via EUIPO, and simple availability check responses rather than raw record sets.

The Official USPTO API: What It Covers

The USPTO trademark search API available through the Open Data Portal provides access to patent and trademark office data including wordmark text, serial and registration numbers, filing date, registration date, update date, owner information (owner_type, legal_entity_type), goods and services descriptions, and international class codes. Results are returned as JSON.

Key capabilities of the official USPTO REST API include serial number search, full-text search across the trademark database, owner search, and retrieval of trademark status (active, abandoned, expired). Developers should note that data freshness depends on how frequently USPTO publishes updates, so check the changelog on the Open Data Portal before building anything latency-sensitive.

Practical limitations exist. Large result sets require batch processing and pagination. Authentication typically requires an API key tied to a USPTO.gov account. The official API is well-suited for due diligence tools, research projects, and applications that need bulk access to raw US trademark data. It does not cover EU trademarks (EUIPO) or provide phonetic matching out of the box.

Tools like Postman can help you prototype requests against the USPTO API endpoint before you integrate it into production code. The base URL structure follows standard REST conventions, and the API overview documentation on USPTO.gov describes available query parameters and response schemas.

The Endpoints Behind tmsearch.uspto.gov and TMview

Many developers arrive here after inspecting the network tab on the official search tools. The USPTO's own interface at tmsearch.uspto.gov drives its results through an internal search-results endpoint that is not a documented public API: it is unversioned, requires no key but throttles aggressively, and its response shape changes without notice. It works for a quick experiment and breaks in production, which is why the documented Open Data Portal API above is the sanctioned route for US data.

The EU picture is similar. TMview at tmdn.org/tmview is the EUIPO's cross-register search covering EU trade marks plus participating national registers, and its browser interface calls an internal api.tmdn.org criteria endpoint. EUIPO does publish official developer APIs, but access runs through registration on the EUIPO API portal rather than the endpoints the website itself uses.

The practical trade-off: scraping the internal endpoints of either register means adopting an undocumented interface that can change any week. Building against the official APIs means two registration processes, two auth models, and two response formats. The Startup Name Generator API and MCP server exists as the third option: one call that screens both the US and EU registers and returns a single normalized answer, maintained so you do not have to track either register's internals.

How the Startup Name Generator API Works

Startup Name Generator exposes an MCP server and HTTP API at /mcp that AI agents and developer tools can call directly. It supports three operations as tools: name generation, .com domain availability checking against live domain records, and US plus EU trademark screening in a single request.

The trademark screening endpoint checks a name against both the USPTO trademark database and the EUIPO registry using exact matching, phonetic matching, and fuzzy matching, plus a domain and linguistic screen. This means one API call can surface potential conflicts that a simple keyword search against the official USPTO endpoint would miss, such as phonetically similar marks registered under a different spelling.

Because the tool covers both the United States Patent and Trademark Office and the EU registry in one query, it is useful for founders and developers building due diligence workflows who need more than raw record retrieval. See the MCP and API documentation for endpoint details and integration specs.

The trademark screen is an automated registry search. It is not legal advice and does not constitute a clearance opinion. For any mark you intend to file, consult a qualified trademark attorney before proceeding.

Trademark Availability Check: What the Automated Screen Covers

When you run a Trademark Check on Startup Name Generator, the system queries the USPTO trademark database and the EUIPO registry, applies exact, phonetic, and fuzzy matching against active trademarks and pending filings, and also checks .com domain availability and flags any linguistic issues with the name.

This is a materially different scope than a basic serial number lookup or keyword search against the official USPTO endpoint. Phonetic matching catches marks that sound like your candidate name even if the spelling differs, which matters because trademark law considers confusingly similar marks, not just identical ones. For background on that distinction, see the guide on identical vs. confusingly similar marks.

Every name the generator surfaces has already had its .com checked against live domain records at generation time, so the availability data is not stale index data. A free trademark search for a specific name is also available through the site's Trademark Check tool.

Pricing and Access

Name generation is free and requires no login to start. The first Trademark Check for an email address is free, once ever. There are no daily or monthly free checks after that initial one. Additional Trademark Checks come from a Launch Pack or a subscription. See the pricing page for current plan details, as specific amounts are not stated here because they change.

For API access, the /mcp endpoint is available to developers and AI agent builders. Authentication and rate limit details are covered in the API documentation at /mcp. If you are evaluating the tool against other options, the knockout trademark search guide explains where automated screening fits in a broader clearance workflow.

Questions, answered

Keep going

• How to Search the USPTO Trademark Database
• Knockout Trademark Search: What It Is and How to Do One
• EU Trademark Search: The Free Official Route, Step by Step
• Free Trademark Search: US Register, Any Name, No Login

Trademark results are an automated database search against the USPTO and EUIPO registries, not legal advice and not a clearance opinion. Registries change daily; results are dated. Before filing, have counsel run full clearance.