Refactor Capital
Refactor Capital is a Bay Area seed fund run by solo general partner Zal Bilimoria, who backs hard-tech founders building in the physical world. Water is not its theme but reaches it through wastewater and green chemistry. As of 2026 Refactor has backed 3 water companies across 3 deals and is investing from its fifth fund.
Compiled by Antoine Walter, (don't) Waste Water, from official filings and direct intelligence in Leviathan.
The take
Refactor Capital began in 2016 as a partnership between Zal Bilimoria, a former Andreessen Horowitz partner who had built products at Google, Netflix and LinkedIn, and David Lee, the longtime head of the seed firm SV Angel. When Lee stepped back to retire in 2018, he asked Bilimoria to keep the firm going alone, and Refactor became one of the rare venture funds run by a single decision-maker, a 'solo GP' who sources, vets and signs every check himself.
Refactor Capital backs founders 'refactoring the real world: atoms, not bits,' which in practice means seed-stage hard tech across applied biology, energy, critical materials, aerospace and health. Bilimoria writes small first checks, usually one to two million dollars, and stays deliberately small, capping his latest fund rather than managing more money than a solo investor reasonably can. Water is nowhere in that thesis as a named category, which is exactly why the water names in the portfolio are worth a closer look.
Refactor Capital's water exposure shows up sideways, through the wastewater stream and through chemistry. Hyfe uses membrane filtration to pull the sugar out of food-factory wastewater, grows it into a mycelium flour, and hands the cleaned water back to the manufacturer. Solugen brews hydrogen peroxide and organic acids that industry and municipalities use to treat water. Biobot Analytics reads a city's sewage like a diagnostic, turning wastewater into public-health data. The common thread across all three is treating used water as something to recover and reuse.
As of 2026, Refactor Capital closed its fifth fund, a roughly fifty-million-dollar seed vehicle Bilimoria raised from existing backers in, by his own account, five phone calls. For anyone tracking water, the honest read is that Refactor is a generalist hard-tech fund that keeps drifting into water through its bio and chemistry bets, not a dedicated water investor. The companies to watch are the ones sitting where biology, manufacturing and the water cycle overlap.
Water Commitment Score
Compiled from official filings, third-party records, and direct intelligence from investors and founders, in Leviathan · recomputed monthly · as of Jun 2026.
How they invest
Portfolio · 3 water companies
Invests alongside
Highlighted = profiled on (don't) Waste Water.
Frequently asked
- What does Refactor Capital invest in?
- Refactor Capital invests in seed-stage hard tech: founders building physical products across applied biology, energy, critical materials, aerospace and health. It writes small first checks of one to two million dollars. Water is not a named theme, but reaches the portfolio through wastewater and green-chemistry companies such as Hyfe, Solugen and Biobot Analytics.
- Who runs Refactor Capital?
- Refactor Capital is run by Zal Bilimoria as its solo general partner, meaning he is the firm's only investing partner. He co-founded Refactor in 2016 with David Lee, the former head of the seed firm SV Angel; Lee retired from day-to-day investing in 2018 and stayed on as chairman.
- Is Refactor Capital a water fund?
- Refactor Capital is not a water fund. It is a generalist seed hard-tech investor whose water exposure is a by-product of its biology and chemistry bets. (don't) Waste Water counts 3 water companies across 3 deals in Refactor's portfolio and rates its water commitment Committed.
- What stage does Refactor Capital invest at?
- Refactor Capital invests at the seed stage, typically writing the first institutional check a hard-tech company raises. Solo GP Zal Bilimoria deliberately keeps each fund small, around fifty million dollars, so he can stay the sole decision-maker. As of 2026 Refactor is investing from its fifth fund.
- Where is Refactor Capital based?
- Refactor Capital is based in Burlingame, California, in the San Francisco Bay Area, and has operated as a seed venture firm since 2016. It is run by solo general partner Zal Bilimoria, who invests across the United States in seed-stage hard-tech startups.