Hydrazine Capital

Hydrazine Capital is a venture capital firm set up by Sam Altman in 2012 with his brother Jack Altman, using proceeds from the sale of Loopt. Its first fund was about $20 million, with Peter Thiel as anchor investor.^{Source [1]Source [3]}

Its early fund put about 75% of its capital into Y Combinator companies. It led a $50 million Reddit round in 2014, and it led a $1.6 million seed round for the property valuation startup ValueBase in 2023, when TechCrunch described it as run by Altman and partner Ryan Cohen.^{Source [3]Source [4]}

The firm has raised four funds. The University of Michigan endowment invested $105 million in the second fund and $75 million in the fourth, launched in March 2023, where it was the only outside investor. Forbes reported about $1.7 billion in gross assets across the four funds in 2024.^{Source [1]Source [3]}

Set up in 2012 by Sam Altman and his brother Jack Altman after the sale of Loopt. Its first fund raised about $20 million, anchored by Peter Thiel, and put about 75% of its capital into Y Combinator companies. A fourth fund was launched in March 2023 with the University of Michigan endowment as its only outside investor, and Forbes reported in 2024 that its four funds held about $1.7 billion in gross assets.^{Source [1]Source [3]Source [2]}