Investors / United States / Castle Island Ventures / Co-investors
Castle Island Ventures co-investors
Who invests alongside Castle Island Ventures · Venture capital · Boston, MA, United States
Castle Island Ventures shares at least one checked portfolio company with 140 other investors. It backs companies most often with Andreessen Horowitz (5), a16z Frontier (4) and Blockchain Capital (3), and 100% of its 25 checked companies have another investor VCinfo tracks.
Co-investor network
the 14 firms it shares most with, and the companies they back togetherCircle size is the number of companies shared with Castle Island Ventures; a line joins two co-investors that back at least two companies together.
All co-investors
top 60 of 140, ranked by shared portfolio companiesA co-investor is a firm whose own portfolio page lists a company that Castle Island Ventures' page lists too, both checked against the company's site. It shows who backs the same companies, not who joined the same round. How the data is graded
Get Castle Island Ventures' co-investors as data
Pull this ranked list, Castle Island Ventures' portfolio and any firm's profile through one API key or MCP, compare portfolios side by side, and get an email when Castle Island Ventures adds a company.
Work email, sign-in link by email. Already have an account? Log in- Ask AI5 plain-English investor searches a day
- Full listsEvery portfolio row and two-firm overlap
- API and MCP100 REST or MCP calls a month, one key
- AlertsFollow 5 investors for portfolio and fund changes
$ curl -H "X-API-Key: YOUR_KEY" \
https://api.vcinfo.io/v1/firms/castleisland.vc/coinvestors
# also
GET /v1/firms/castleisland.vc
GET /v1/firms/castleisland.vc/portfolio