Billionaire Democratic donor Tom Steyer’s vehicle for environmental grantmaking has a stake in a private equity firm that is invested in green energy companies, the group confirmed last week.

The TomKat Charitable Trust was “[e]stablished in 2009 with funding from Tom Steyer and Kat Taylor,” according to a spokesman, who said that the nonprofit foundation is a limited partner in BrightPath Capital Partners, L.P.

Kat Taylor is Steyer’s wife.

The firm is invested in at least three green energy companies. One of those companies has received federal subsidies and was under investigation as late as February into whether it misrepresented financial information to obtain those subsidies, documents obtained by the Washington Free Beacon reveal.

Steyer and Taylor put up nearly $175 million to start TomKat in 2008. Since that initial cash infusion, most of TomKat’s revenue has been investment income—more than $72 million, compared with just $2 million in contributions to the group.

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