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Investors / Castle Island Ventures / Compare with F-Prime Capital

Castle Island Ventures vs F-Prime Capital

Castle Island Ventures lists 25 portfolio companies and has joined 15 funding rounds; F-Prime Capital lists 284 companies and has joined 43 rounds. Castle Island Ventures comes in most often at Seed (50% of its entries), F-Prime Capital comes in most often at Series A (49% of its entries). 2 companies are on both portfolios, among them Cyclops and Groma.

25Portfolio companies284
15Funding rounds joined43
7Rounds led11
10Rounds, last 12 months25
$5M to $20MTypical round it comes in at$20M to $100M
0%Sites no longer answering0%
Show as a table
Castle Island Ventures and F-Prime Capital, head to head
Castle Island VenturesF-Prime Capital
Portfolio companies25284
Funding rounds joined1543
Rounds led711
Rounds, last 12 months1025
Typical round it comes in at$5M to $20M$20M to $100M
Sites no longer answering0%0%

Where they come in

share of entries by stage
Pre-seed0%0%
Seed50%10%
Series A42%49%
Series B8%29%
Growth0%12%

Castle Island VenturesF-Prime Capital

Show as a table
Entry stages of Castle Island Ventures and F-Prime Capital, share of entries
Castle Island VenturesF-Prime Capital
Pre-seed0%0%
Seed50%10%
Series A42%49%
Series B8%29%
Growth0%12%

Themes

share of checked companies
Fintech58%20%
Healthcare & Biotech3%42%
AI & Machine Learning3%11%
Cybersecurity11%2%
Crypto & Web311%5%
Real Estate & Construction5%2%

Castle Island VenturesF-Prime Capital

Show as a table
Themes of Castle Island Ventures and F-Prime Capital, share of checked companies
Castle Island VenturesF-Prime Capital
Fintech58%20%
Healthcare & Biotech3%42%
AI & Machine Learning3%11%
Cybersecurity11%2%
Crypto & Web311%5%
Real Estate & Construction5%2%

Companies both back

2

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 F-Prime 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/fprimecapital.com/portfolio
GET /v1/firms/castleisland.vc/coinvestors
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