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Investors / Castle Island Ventures / Compare with Circle Capital

Castle Island Ventures vs Circle Capital

Castle Island Ventures lists 25 portfolio companies and has joined 15 funding rounds; Circle Capital lists 22 companies and has joined 20 rounds. Castle Island Ventures comes in most often at Seed (50% of its entries), Circle Capital comes in most often at Seed (37% of its entries). 1 company is on both portfolios, among them Cyclops.

25Portfolio companies22
15Funding rounds joined20
7Rounds led3
10Rounds, last 12 months15
$5M to $20MTypical round it comes in at$5M to $20M
0%Sites no longer answering0%
Show as a table
Castle Island Ventures and Circle Capital, head to head
Castle Island VenturesCircle Capital
Portfolio companies2522
Funding rounds joined1520
Rounds led73
Rounds, last 12 months1015
Typical round it comes in at$5M to $20M$5M to $20M
Sites no longer answering0%0%

Where they come in

share of entries by stage
Pre-seed0%0%
Seed50%37%
Series A42%26%
Series B8%16%
Growth0%21%

Castle Island VenturesCircle Capital

Show as a table
Entry stages of Castle Island Ventures and Circle Capital, share of entries
Castle Island VenturesCircle Capital
Pre-seed0%0%
Seed50%37%
Series A42%26%
Series B8%16%
Growth0%21%

Themes

share of checked companies
Fintech58%37%
Crypto & Web311%15%
Cybersecurity11%0%
Healthcare & Biotech3%10%
Enterprise Software3%7%
Consumer3%7%

Castle Island VenturesCircle Capital

Show as a table
Themes of Castle Island Ventures and Circle Capital, share of checked companies
Castle Island VenturesCircle Capital
Fintech58%37%
Crypto & Web311%15%
Cybersecurity11%0%
Healthcare & Biotech3%10%
Enterprise Software3%7%
Consumer3%7%

Companies both back

1

Shared 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

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Compare Castle Island Ventures and Circle Capital 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.

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  • 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
VCinfo API
$ curl -H "X-API-Key: YOUR_KEY" \
  https://api.vcinfo.io/v1/firms/castleisland.vc/portfolio

# also
GET /v1/firms/circle.vc/portfolio
GET /v1/firms/castleisland.vc/coinvestors
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