Superstar investor Peter Thiel launched a new fund today called Mithril Capital Management that’s already raised $402 million for late-stage investments in private companies.

Mithril (yes, it is named after the light-but-strong substance from the Lord of the Rings) will focus on companies that want to remain private as they grow into big businesses. Thiel’s involvement brings extra attention to Mithril, having co-founded PayPal, invested early in Facebook, and created both Clarium Capital and Founders Fund.

“Technology holds the solution to most of the world’s most pressing challenges, from resource scarcity to disease. A great achievement may require a decade of work, but a lifetime of vision,” Thiel said in a statement. “Mithril will play a patient, focused, and pivotal role in helping the world’s most outstanding creative minds solve vexing problems and build lasting companies.”

While Thiel is Mithril’s founding and largest individual investor, the Mithril team will be headed up by co-founder Ajay Royan, who has worked with Thiel on various projects since 2003, including a stint as managing director at Clarium. Royan sees Mithril as a chance to invest in companies that change the format of how things are done.

“Many great inventions are driven by a spirit of dissent and curiosity,” said Royan. “That spirit defines and pervades Silicon Valley, but it can be found everywhere in the world. Just as Sony inaugurated the age of personal media, Skype made peer communications compete with telecoms, and ARM redefined efficient mobile computing, Mithril companies, if we’re right, will foment changes that will seem inevitable after they happen.”

Mithril shirt photo: Lord of the Rings