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Investors / Old Main Ventures / Co-investors

Old Main Ventures co-investors

Who invests alongside Old Main Ventures · Venture capital

Old Main Ventures shares at least one checked portfolio company with 5 other investors. It backs companies most often with Astia (1), Borderless Capital (1) and Castle Island Ventures (1), and 100% of its 3 checked companies have another investor VCinfo tracks.

Old Main Ventures' full profileCompare with AstiaGET /v1/firms/oldmainvc.com/coinvestors
5co-investors
3companies backed with another investorof 3 checked
100%of its portfolio is co-backed
Astiamost frequent co-investor1 shared company

Co-investor network

the 5 firms it shares most with, and the companies they back together
5 shared companiesAstia: 1 shared companiesAstia1Borderless Capital: 1 shared companiesBorderless Capital1Castle Island Ventures: 1 shared companiesCastle Island Ventures1RET Ventures: 1 shared companiesRET Ventures1Second Century Ventures: 1 shared companiesSecond Century Ventur…1
Shared portfolio companies with Old Main VenturesFirms that also back companies together

Circle size is the number of companies shared with Old Main Ventures; a line joins two co-investors that back at least two companies together.

All co-investors

ranked by shared portfolio companies
#InvestorSharedCompanies both back
1AstiaVenture capital · United States1
Light Line Medical
Compare · Its co-investors
2Borderless CapitalVenture capital · United States1
Attestiv
Compare · Its co-investors
3Castle Island VenturesVenture capital · United States1
Attestiv
Compare · Its co-investors
4RET VenturesVenture capital · United States1
PredictAP
Compare · Its co-investors
5Second Century VenturesVenture capital · United States1
PredictAP
Compare · Its co-investors
Take this list with you. GET /v1/firms/oldmainvc.com/coinvestors returns the ranked list as JSON for a CRM, a sheet or an AI agent: 25 firms a call on the free plan, 100 on Pro.
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A co-investor is a firm whose own portfolio page lists a company that Old Main Ventures' page lists too, both checked against the company's site. It shows who backs the same companies, not who joined the same round. How the data is graded

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Get Old Main Ventures' co-investors as data

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VCinfo API
$ curl -H "X-API-Key: YOUR_KEY" \
  https://api.vcinfo.io/v1/firms/oldmainvc.com/coinvestors

# also
GET /v1/firms/oldmainvc.com
GET /v1/firms/oldmainvc.com/portfolio
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