Peter Thiel's Founders Fund is closing its fourth growth fund, Founders Fund Growth IV, with $6 billion in commitments. The fund is largely funded by outside investors, with about $1.5 billion of this funding coming from Founders Fund's partners. This comes less than a year after Founders Fund closed its third growth fund. The firm has a portfolio of winning startups, including Crusoe, Rippling, and Palantir Technologies. It also holds stakes in defense tech companies such as SpaceX, Flock Safety, and Anduril.