Keiretsu Forum is the world's largest angel investor network, comprising over 3,000 accredited investors across 56 chapters worldwide. Founded in 2000 by Randy Williams in San Francisco, the network has invested over $1 billion in more than 1,000 vetted startups. Members include active private equity investors, business leaders, serial entrepreneurs, venture capitalists, corporate investment divisions, and family offices.

They focus on early-stage investments in sectors such as technology, consumer goods, internet, healthcare, life sciences, energy, real estate, and high-growth entrepreneurship. Keiretsu Forum is recognized for its rigorous screening process, extensive due diligence, and collaborative investment approach, leading Pitchbook to name it the #1 most active global investor by deal count. The network operates on a referral model, charging entrepreneurs fees for the opportunity to pitch to members, a practice that has been subject to

and discussion within the angel investing community.