Propeller
Propeller is a Boston-based venture fund investing at the ocean-climate nexus, from pre-seed to Series A. Co-founded in 2022 by HubSpot's Brian Halligan, its $118M Fund I backs ocean industrials, marine carbon removal, and ocean-derived food across 23 investments; (don't) Waste Water tracks two of them as water bets.
Compiled by Antoine Walter, (don't) Waste Water, from official filings and direct intelligence in Leviathan.
The take
Propeller is the ocean-climate fund that bolts software investors onto ocean science. It was co-founded in 2022 by HubSpot's Brian Halligan and the lifelong ocean entrepreneur Reece Pacheco, and it launched in partnership with the Woods Hole Oceanographic Institution, the storied research lab on Cape Cod. The bet is simple and contrarian: that the ocean, not just land and air, is one of the biggest levers on climate, and almost nobody is funding it.
Propeller invests across three themes it calls Ocean Industrials, Carbon, and Organics: the maritime energy, shipping, robotics and automation that move on the water; the technologies that pull carbon out of the sea or stop it going in; and the food, feed and fertilizer that come from it. It writes early cheques, from pre-seed to Series A, into companies that are in, on, around or adjacent to the ocean, and its partners are all former operators rather than career financiers.
Propeller's water-facing bets show the pattern. (don't) Waste Water tracks two of its portfolio companies across two deals: Aquatic Labs, a Cambridge sensor maker building in-situ instruments that read seawater chemistry like alkalinity and pH in real time, and Olokun Minerals, which runs modular electrochemical systems on seawater to pull out the minerals the energy transition needs. Propeller invests alongside the small club of water-native funds, among them Burnt Island Ventures and Counteract Partners, which is how these unglamorous ocean-chemistry companies get funded at all.
Propeller is what climate venture looks like when you take the ocean seriously as an asset class rather than a backdrop. With a $118M first fund and 23 investments already made, the open question I am watching is how many of its next bets read as water, the sensors, treatment and mineral-recovery plays, versus the shipping and carbon themes that compete for the same early cheques.
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 · 2 water companies
Invests alongside
Highlighted = profiled on (don't) Waste Water.
Frequently asked
- What does Propeller Ventures invest in?
- Propeller invests at the ocean-climate nexus, backing early-stage companies in, on or around the sea across three themes: Ocean Industrials, Carbon, and Organics. In water specifically, (don't) Waste Water tracks two of its companies, the seawater-sensor maker Aquatic Labs and the ocean-mineral firm Olokun Minerals, across two deals.
- Who runs Propeller Ventures?
- Propeller was co-founded in 2022 by HubSpot co-founder Brian Halligan, ocean entrepreneur Reece Pacheco, and CRV general partner Devdutt Yellurkar. Reece Pacheco leads day-to-day investing, alongside managing partners Rodrigo Prudencio, a former Amazon Climate Pledge Fund co-founder, and Steven Fox.
- How big is Propeller Ventures?
- Propeller is investing from Fund I, a $118 million vehicle raised in 2022 and focused on pre-seed to Series A ocean-climate startups. The fund has made 23 investments to date; (don't) Waste Water tracks two of them, both water companies, across two deals.
- Where is Propeller Ventures based?
- Propeller is based in Boston, Massachusetts, and invests globally in companies working in, on, around or adjacent to the ocean. It launched in 2022 in partnership with the Woods Hole Oceanographic Institution, the research lab on Cape Cod, which anchors its ocean-science network.
- Is Propeller Ventures the same as Propeller Aero or Propeller Industries?
- No. Propeller Ventures is the Boston ocean-climate venture fund described here. It is unrelated to Propeller Aero, a drone-mapping company for mining and construction, and to Propeller Industries, an outsourced-finance firm. The name is shared; the businesses are not.