Investors / 645 Ventures / Compare with Castle Island Ventures
645 Ventures vs Castle Island Ventures
645 Ventures lists 81 portfolio companies and has joined 25 funding rounds; Castle Island Ventures lists 25 companies and has joined 15 rounds. 645 Ventures comes in most often at Series A (46% of its entries), Castle Island Ventures comes in most often at Seed (50% of its entries). 1 company is on both portfolios, among them Andrena.
Show as a table
| 645 Ventures | Castle Island Ventures | |
|---|---|---|
| Portfolio companies | 81 | 25 |
| Funding rounds joined | 25 | 15 |
| Rounds led | 5 | 7 |
| Rounds, last 12 months | 17 | 10 |
| Typical round it comes in at | $20M to $100M | $5M to $20M |
| Sites no longer answering | 0% | 0% |
Where they come in
share of entries by stage645 VenturesCastle Island Ventures
Show as a table
| 645 Ventures | Castle Island Ventures | |
|---|---|---|
| Pre-seed | 0% | 0% |
| Seed | 38% | 50% |
| Series A | 46% | 42% |
| Series B | 8% | 8% |
| Growth | 8% | 0% |
Themes
share of checked companies645 VenturesCastle Island Ventures
Show as a table
| 645 Ventures | Castle Island Ventures | |
|---|---|---|
| Fintech | 12% | 58% |
| AI & Machine Learning | 30% | 3% |
| Cybersecurity | 9% | 11% |
| Crypto & Web3 | 0% | 11% |
| Enterprise Software | 9% | 3% |
| Healthcare & Biotech | 7% | 3% |
Companies both back
1Shared companies are those both firms' own portfolio pages list, each checked against the company's site. The same comparison through the API is POST /v1/overlap, for up to 20 firms. How the data is graded
Compare 645 Ventures and Castle Island Ventures as data
Pull both portfolios and every co-investor through one API key or MCP, and lay up to 20 firms side by side with POST /v1/overlap. A free account adds Ask AI searches and alerts when either firm 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/645ventures.com/portfolio
# also
GET /v1/firms/castleisland.vc/portfolio
GET /v1/firms/645ventures.com/coinvestors