Limited partners include Allen & Co., which also served as placement agent.

Don’t expect this to be another in a long line a recent growth equity funds whose mission is to participate in Series G rounds for the next Groupon or Zynga. Instead, Mithril is seeking more unusual targets that, for the most part, don’t have any immediate IPO plans. In fact, the holding periods might be closer to that of Founders Fund.

Ajay Royan, an ex-Clarium hand who will serve as Mithril’s managing general partner, explained it thusly: “In a perfect world, we could create a Berkshire Hathaway for growth companies. Obviously we can’t do that, but we think this strategy is the next best thing… We really want to help drive growth for companies that are past the traditional venture stage, but where our involvement can still make a significant difference.”

Royan and Thiel are the two senior investing partners, while the entire team right now is seven people. And, yes, Mithril is a fictional metal from the Lord of the Rings universe. Royan says he and Thiel are big Tolkien fans, and that mithril is “rare, protective and transformative.”

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