OpenSOSData – US Business Entity Search MCP server

OpenSOSData MCP Server

Real-time US business entity search for Claude. Search, verify, and check the status of any LLC, corporation, or registered entity across all 53 US jurisdictions directly from your Claude conversation.

The only business entity search MCP with complete US coverage: all 50 states + Washington DC + Puerto Rico + US Virgin Islands.

What You Can Do

Ask Claude things like:

• "Is Stripe Inc registered as a corporation in Delaware?"
• "Search for any LLC named Apex Consulting in Texas, Florida, and New York"
• "Verify these 5 vendors are properly registered" (batch check)
• "What states does OpenSOSData cover?"
• "Check if this company is active or dissolved in California"

Connect via Claude.ai

1. Go to claude.ai/connectors
2. Find OpenSOSData
3. Connect with your API key from opensosdata.com

Install via Claude Desktop or Claude Code

Add to your claudedesktopconfig.json:

{
  "mcpServers": {
    "opensosdata": {
      "command": "npx",
      "args": ["-y", "@opensosdata/mcp-server"],
      "env": {
        "OPENSOSDATA_API_KEY": "your-api-key-here"
      }
    }
  }
}

Get your API key at opensosdata.com. 10 free lookups included on signup. No credit card required.

Remote MCP Server (No Installation)

Connect directly without installing anything:

https://mcp.opensosdata.com/mcp

Pass your OpenSOSData API key as a Bearer token in the Authorization header.

Available Tools

All tools are read-only (readOnlyHint: true). No data is modified.

Usage Examples

Example 1: KYB Verification

You: "Is Stripe Inc registered as a corporation in Delaware?"

Claude: Calls checkentitystatus with entity_name="Stripe" and state="DE", returns confirmation that Stripe is active and registered, with entity ID and filing details.

Example 2: Multi-State Due Diligence

You: "Search for any LLC named Apex Consulting in Texas, Florida, and New York"

Claude: Calls batch_search with three entries, returns all matching entities across all three states with their current status.

Example 3: Vendor Verification

You: "Verify these vendors are properly registered:

• Acme Corp in California
• Summit LLC in Georgia
• Pinnacle Inc in Illinois"

Claude: Calls batch_search, returns active/inactive status for each vendor with entity IDs for your records.

Example 4: Regional Compliance Check

You: "What jurisdictions should I check for a company doing business across the Southeast?"

Claude: Calls getjurisdictionsfor_region with region="southeast", returns all Southeast states so you know exactly which registries to verify.

Example 5: Territory Coverage

You: "Does this API cover Puerto Rico and DC?"

Claude: Calls listsupportedjurisdictions, confirms coverage of all 53 jurisdictions including DC, Puerto Rico, and US Virgin Islands.

Coverage

53 US jurisdictions with live, real-time data:

• All 50 US states including Kansas
• Washington DC (corponline.dlcp.dc.gov)
• Puerto Rico (rcp.estado.pr.gov)
• US Virgin Islands (corporationsandtrademarks.vi.gov)

Data is fetched live from official Secretary of State portals at query time. Not a stale database.

Shortened. The full README is on GitHub.