Justin Mateen is the Founder and Managing Partner of JAM Fund. See portfolio, sector focus and contact routes.
Justin Mateen is the Founder and Managing Partner of JAM Fund, an early-stage venture capital firm based in Los Angeles, and previously served as Chief Marketing Officer and co-founder of Tinder[2][3]. His investment thesis targets pre-seed and seed-stage companies in consumer technology, financial technology, enterprise software, social platforms, and marketplaces, with a strategic focus on geographic arbitrage in emerging markets[3][12]. Typical check sizes range from $500,000 to $20 million, and Mateen operates as a solo general partner who serves as the primary decision-maker and lead investor[12]. Notable portfolio companies include fintech unicorns Brex and Deel, as well as early bets on Lyft and investments in Kalshi, Whop, and Curative[3][6][9]. Mateen is recognized as a serial seed investor who backs underestimated founders with “something to prove” and emphasizes hands-on portfolio management[6][12]. He has been featured in Business Insider’s Tribe Capital Seed 100 and Forbes’ Founders Under 30, reflecting his prominence in early-stage tech investing[5].
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