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Investors / 1kx / Compare with Castle Island Ventures

1kx vs Castle Island Ventures

1kx lists 73 portfolio companies and has joined 15 funding rounds; Castle Island Ventures lists 25 companies and has joined 15 rounds. 1kx comes in most often at Seed (50% of its entries), Castle Island Ventures comes in most often at Seed (50% of its entries). 1 company is on both portfolios, among them arxresearch.com.

73Portfolio companies25
15Funding rounds joined15
7Rounds led7
6Rounds, last 12 months10
$5M to $20MTypical round it comes in at$5M to $20M
0%Sites no longer answering0%
Show as a table
1kx and Castle Island Ventures, head to head
1kxCastle Island Ventures
Portfolio companies7325
Funding rounds joined1515
Rounds led77
Rounds, last 12 months610
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%50%
Series A29%42%
Series B14%8%
Growth7%0%

1kxCastle Island Ventures

Show as a table
Entry stages of 1kx and Castle Island Ventures, share of entries
1kxCastle Island Ventures
Pre-seed0%0%
Seed50%50%
Series A29%42%
Series B14%8%
Growth7%0%

Themes

share of checked companies
Fintech34%58%
Crypto & Web315%11%
Cybersecurity9%11%
Enterprise Software10%3%
AI & Machine Learning6%3%
Gaming6%0%

1kxCastle Island Ventures

Show as a table
Themes of 1kx and Castle Island Ventures, share of checked companies
1kxCastle Island Ventures
Fintech34%58%
Crypto & Web315%11%
Cybersecurity9%11%
Enterprise Software10%3%
AI & Machine Learning6%3%
Gaming6%0%

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 1kx and Castle Island 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/1kx.capital/portfolio

# also
GET /v1/firms/castleisland.vc/portfolio
GET /v1/firms/1kx.capital/coinvestors
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