Rainmatter is a perpetual investment fund launched by Zerodha (India's largest stock brokerage) in 2016, backing Indian founders across fintech, climate, health, and media. Unlike a traditional VC fund, Rainmatter is not stage-based, takes no board seats, and has no active exit mandate — it reinvests a portion of Zerodha's own earnings as patient, long-term capital rather than raising from external LPs against a fund-life clock.