USPTO

USPTO Patent Assignment Search API

The USPTO Patent Assignment Search API retrieves patent assignment information including ownership transfers, recorded assignments, and assignment history for individual patents and patent portfolios.

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Documentation

📖
Documentation
https://developer.uspto.gov/api-catalog

Other Resources

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APIsJSON
https://raw.githubusercontent.com/api-evangelist/uspto/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: uspto:assignment-search-api
name: USPTO Patent Assignment Search API
description: The USPTO Patent Assignment Search API retrieves patent assignment information including
  ownership transfers, recorded assignments, and assignment history for individual patents and patent
  portfolios.
tags:
- Assignments
- Government
- Patents
- Regulatory
humanURL: https://developer.uspto.gov/api-catalog
properties:
- type: Documentation
  url: https://developer.uspto.gov/api-catalog