Introduction
SOSfinder gives you Secretary of State business-entity data for all 50 states through a single REST endpoint — entity status, registered agent, formation date, and more.
Every lookup goes through one unified endpoint. Pass a business name and a state, and SOSfinder returns the best match plus similar filings in one consistent schema for every state.
Quickstart
Authenticate with your secret key from the server side and GET /search with a state and a business name.
curl 'https://api.sosfinder.com/search?state=WY&business_name=Acme%20LLC' \
-H "x-api-key: $SOS_API_KEY"