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Investors / Castle Island Ventures / Compare with Operator Partners

Castle Island Ventures vs Operator Partners

Castle Island Ventures lists 25 portfolio companies and has joined 15 funding rounds; Operator Partners lists 171 companies and has joined 22 rounds. Castle Island Ventures comes in most often at Seed (50% of its entries), Operator Partners comes in most often at Series A (50% of its entries). 2 companies are on both portfolios, among them Fireblocks Dynamic and TRM Labs.

25Portfolio companies171
15Funding rounds joined22
7Rounds led1
10Rounds, last 12 months15
$5M to $20MTypical round it comes in at$20M to $100M
0%Sites no longer answering0%
Show as a table
Castle Island Ventures and Operator Partners, head to head
Castle Island VenturesOperator Partners
Portfolio companies25171
Funding rounds joined1522
Rounds led71
Rounds, last 12 months1015
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%23%
Series A42%50%
Series B8%23%
Growth0%5%

Castle Island VenturesOperator Partners

Show as a table
Entry stages of Castle Island Ventures and Operator Partners, share of entries
Castle Island VenturesOperator Partners
Pre-seed0%0%
Seed50%23%
Series A42%50%
Series B8%23%
Growth0%5%

Themes

share of checked companies
Fintech58%18%
AI & Machine Learning3%18%
Healthcare & Biotech3%17%
Cybersecurity11%8%
Crypto & Web311%0%
Enterprise Software3%9%

Castle Island VenturesOperator Partners

Show as a table
Themes of Castle Island Ventures and Operator Partners, share of checked companies
Castle Island VenturesOperator Partners
Fintech58%18%
AI & Machine Learning3%18%
Healthcare & Biotech3%17%
Cybersecurity11%8%
Crypto & Web311%0%
Enterprise Software3%9%

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 Operator Partners 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/operatorpartners.com/portfolio
GET /v1/firms/castleisland.vc/coinvestors
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