All Aboard closes $133M fund for climate's missing middle

The All Aboard Coalition closed its debut fund at $133 million, giving a group of venture and growth investors a shared vehicle for climate technologies at a difficult stretch of their development. The coalition formed in 2025 with 14 firms whose combined assets topped $60 billion; it has since grown to 20 members. ESG Today first reported the final close on August 18, 2026.

The fund's target is what the group calls the missing middle. A climate company can often raise venture money while its technology is unproven, and infrastructure capital once the technology is proven. The expensive period in between — first commercial deployments and early scale-up work — is where deals stall. All Aboard Fund I is structured as a co-investment vehicle: it commits capital only after three or more qualifying member firms have each independently decided to put meaningful money into the same financing round. As the group describes it, the fund benefits from multiple independent investment committees before it writes a check.

The model is designed to do more than clear a due diligence hurdle. By gathering those independent decisions, All Aboard can help assemble the large syndicates that capital-intensive projects require, and it can connect venture capital, growth capital, and eventually infrastructure investors in the same round. The missing middle is hard partly because risk is concentrated; the coalition's answer is to spread it across a group that has already backed the project with its own money.

At the close, the fund added a strategic partner. Macdoch, the family office and investment and philanthropic platform of Prue and Alasdair MacLeod, has become a significant investor in Fund I and a member of All Aboard Investment Management Company, the fund's investment manager. The arrangement also sets up a framework for Macdoch to participate in the economics and governance of future All Aboard vehicles. How significant Macdoch's stake is not disclosed. Macdoch's seat inside the manager suggests the model is meant to run more than one fund.

Stan Miranda, All Aboard's co-founder and CEO of the True North Institute, describes the bottleneck as having shifted. "Macdoch brings much more to All Aboard than capital," he said. "They share our belief that one of the central challenges in climate investing is no longer simply identifying promising technologies but helping the best of those technologies cross the difficult gap from venture-backed innovation to commercial scale."

The fund has completed three investments so far, most recently in Antora, an energy storage technology company. The names of the other two are not included in ESG Today's report.

There is a deliberate constraint in that design. All Aboard cannot be the first money into a deal; it can only move once several other investors have already decided to move. That buys protection against bad rounds and costs speed. The tension is real: the structure that gives the fund its discipline may also be the structure that slows it down.

Macdoch's seat inside the manager could help on that front. A family office with a stake across future All Aboard vehicles is a repeat source of capital that does not have to be re-sold on each new round. What matters more is that a family office in the governance layer gives the fund a patient anchor when the syndicate needs one. Whether that is enough to bring infrastructure investors into subsequent syndicates is the model's open question.

For a first-time fund, $133 million is a reasonable proving ground, and it is enough to make All Aboard a meaningful participant in several rounds. The long-term test is whether the coalition model can scale beyond its current members. All Aboard has built a disciplined way to share risk; the missing middle will still be missing if the infrastructure money never shows up.