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Investors / Castle Island Ventures / Compare with Unpopular Ventures

Castle Island Ventures vs Unpopular Ventures

Castle Island Ventures lists 25 portfolio companies and has joined 15 funding rounds; Unpopular Ventures lists 19 companies and has joined 4 rounds. Castle Island Ventures comes in most often at Seed (50% of its entries), Unpopular Ventures comes in most often at Seed (100% of its entries). 1 company is on both portfolios, among them Felix.

25Portfolio companies19
15Funding rounds joined4
7Rounds led0
10Rounds, last 12 months2
$5M to $20MTypical round it comes in at$5M to $20M
0%Sites no longer answering0%
Show as a table
Castle Island Ventures and Unpopular Ventures, head to head
Castle Island VenturesUnpopular Ventures
Portfolio companies2519
Funding rounds joined154
Rounds led70
Rounds, last 12 months102
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%100%
Series A42%0%
Series B8%0%
Growth0%0%

Castle Island VenturesUnpopular Ventures

Show as a table
Entry stages of Castle Island Ventures and Unpopular Ventures, share of entries
Castle Island VenturesUnpopular Ventures
Pre-seed0%0%
Seed50%100%
Series A42%0%
Series B8%0%
Growth0%0%

Themes

share of checked companies
Fintech58%13%
AI & Machine Learning3%29%
Education0%13%
Cybersecurity11%0%
Crypto & Web311%0%
Healthcare & Biotech3%10%

Castle Island VenturesUnpopular Ventures

Show as a table
Themes of Castle Island Ventures and Unpopular Ventures, share of checked companies
Castle Island VenturesUnpopular Ventures
Fintech58%13%
AI & Machine Learning3%29%
Education0%13%
Cybersecurity11%0%
Crypto & Web311%0%
Healthcare & Biotech3%10%

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 Unpopular 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.

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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/unpopular.vc/portfolio
GET /v1/firms/castleisland.vc/coinvestors
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