Jack Altman joins Benchmark as GP

Jack Altman and Benchmark announced today that he will join the firm as a general partner.

This news is important, especially since Altman has been running his own firm, Alt Capital, since at least 2024. The fund raised a $150 million fund in early 2024, then last September announced a $274 million fund, raised in just one week. On LinkedIn, Altman called the past two years running Alt Capital as an investor “the most rewarding” of his life, adding that he loved “new ideas and being part of a team with a mission.”

Alt Capital has invested in at least 52 companies, according to PitchBook, including Rippling, Antares Nuclear and CompLabs. It’s unclear what happens to Alt Capital or whether Benchmark has acquired its portfolio, as Altman also announced that his fellow fund mates will follow him to Benchmark. (This is also unusual, since Benchmark has historically been structured as a flat firm with primarily general practitioners only, versus layers of investors.)

Altman also said he would retain board seats at companies he backed while at Alt Capital.

Altman did not respond to requests for comment earlier today; Benchmark declined to comment.

Altman, the younger brother of OpenAI co-founder Sam, is also the founder of HR platform Lattice, which he still heads, according to his LinkedIn profile.