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Investors / a16z Frontier / Compare with Castle Island Ventures

a16z Frontier vs Castle Island Ventures

a16z Frontier lists 119 portfolio companies and has joined 20 funding rounds; Castle Island Ventures lists 25 companies and has joined 15 rounds. a16z Frontier comes in most often at Seed (47% of its entries), Castle Island Ventures comes in most often at Seed (50% of its entries). 4 companies are on both portfolios, among them Babylon, Fireblocks Dynamic and Felix.

119Portfolio companies25
20Funding rounds joined15
11Rounds led7
12Rounds, last 12 months10
$20M to $100MTypical round it comes in at$5M to $20M
0%Sites no longer answering0%
Show as a table
a16z Frontier and Castle Island Ventures, head to head
a16z FrontierCastle Island Ventures
Portfolio companies11925
Funding rounds joined2015
Rounds led117
Rounds, last 12 months1210
Typical round it comes in at$20M to $100M$5M to $20M
Sites no longer answering0%0%

Where they come in

share of entries by stage
Pre-seed0%0%
Seed47%50%
Series A27%42%
Series B13%8%
Growth13%0%

a16z FrontierCastle Island Ventures

Show as a table
Entry stages of a16z Frontier and Castle Island Ventures, share of entries
a16z FrontierCastle Island Ventures
Pre-seed0%0%
Seed47%50%
Series A27%42%
Series B13%8%
Growth13%0%

Themes

share of checked companies
Fintech41%58%
Crypto & Web312%11%
Enterprise Software11%3%
Cybersecurity4%11%
AI & Machine Learning9%3%
Real Estate & Construction0%5%

a16z FrontierCastle Island Ventures

Show as a table
Themes of a16z Frontier and Castle Island Ventures, share of checked companies
a16z FrontierCastle Island Ventures
Fintech41%58%
Crypto & Web312%11%
Enterprise Software11%3%
Cybersecurity4%11%
AI & Machine Learning9%3%
Real Estate & Construction0%5%

Companies both back

4

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 a16z Frontier 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/a16zfrontier.com/portfolio

# also
GET /v1/firms/castleisland.vc/portfolio
GET /v1/firms/a16zfrontier.com/coinvestors
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