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Investors / Castle Island Ventures / Compare with Markham Valley Ventures

Castle Island Ventures vs Markham Valley Ventures

Castle Island Ventures lists 25 portfolio companies and has joined 15 funding rounds; Markham Valley Ventures lists 7 companies and has joined 3 rounds. Castle Island Ventures comes in most often at Seed (50% of its entries), Markham Valley Ventures comes in most often at Series B (67% of its entries). 1 company is on both portfolios, among them OpenFX.

25Portfolio companies7
15Funding rounds joined3
7Rounds led0
10Rounds, last 12 months3
$5M to $20MTypical round it comes in at$20M to $100M
0%Sites no longer answering0%
Show as a table
Castle Island Ventures and Markham Valley Ventures, head to head
Castle Island VenturesMarkham Valley Ventures
Portfolio companies257
Funding rounds joined153
Rounds led70
Rounds, last 12 months103
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%33%
Series A42%0%
Series B8%67%
Growth0%0%

Castle Island VenturesMarkham Valley Ventures

Show as a table
Entry stages of Castle Island Ventures and Markham Valley Ventures, share of entries
Castle Island VenturesMarkham Valley Ventures
Pre-seed0%0%
Seed50%33%
Series A42%0%
Series B8%67%
Growth0%0%

Themes

share of checked companies
Fintech58%23%
Healthcare & Biotech3%23%
Cybersecurity11%0%
Crypto & Web311%0%
AI & Machine Learning3%8%
Education0%8%

Castle Island VenturesMarkham Valley Ventures

Show as a table
Themes of Castle Island Ventures and Markham Valley Ventures, share of checked companies
Castle Island VenturesMarkham Valley Ventures
Fintech58%23%
Healthcare & Biotech3%23%
Cybersecurity11%0%
Crypto & Web311%0%
AI & Machine Learning3%8%
Education0%8%

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 Markham Valley 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
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  • 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/markham.vc/portfolio
GET /v1/firms/castleisland.vc/coinvestors
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