Who invested in Rainmaker

3 rounds we have observed, with the 9 investors named in them. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it.

Consumer AppsCleantechClimate TechWater

Raised 1 month agoY Combinator: W23

Funding summaryUpdated 26 Oct 2026

$126Mraised across 3 rounds since 2023, from 5 sources

$500KPre-seed$25MSeries A$100MSeries B

Latest round: Series B, $100MSept 2026
Step-upi: 4×
Investors: 9

See who backed them

The funding story

Each circle is a round, placed by date and sized by amount. The line above is the running total.

202420252026

$500KPre-seed$25MSeries A$100MSeries B

First round: Pre-seed, $500K
Biggest round: $100M
Usual gap between rounds: 2.1 years

The rounds

Sept 2026
Series B$100M5 new2 returning
Reported by TechStartups and 2 others
May 2025
Series A$25M3 new
Source recorded
Apr 2023
Pre-seed$500K1 new
- Y Combinator
Source recorded

Who was in which round

The busiest backers across the latest rounds. A filled square is a round they joined; a dark one, a round they led.

Pre-seed2023Series A2025Series B2026

Long Journey Ventures

Everyone who backed them

Long Journey VenturesVC firm2rounds

Lowercarbon CapitalVC firm2rounds

Y CombinatorAccelerator1round

DCVCVC firm1round

Upfront VenturesVC firm1round

M VenturesCorporate VC1round

1517 FundVC firm1round

NoaVC firm1round

Dream VenturesVC firm1round

Missing a round, or an investor who was in one? Tell us.

Also claim to have backed them

These 6 firms list Rainmaker as a portfolio company on their own websites, but no report of a round names them. They are the firms' own claims, kept apart from the rounds above.