It's not every day that a billionaire hedge fund manager takes to social media to recommend a biography. But on Sunday, Pershing Square Capital Management founder Bill Ackman did exactly that, throwing his support behind "The Philosopher in the Valley: Alex Karp, Palantir and the Rise of the Surveillance State," Michael Steinberger's new book about the Palantir Technologies (PLTR) CEO.

A Quick, Fascinating Read

Writing on X, Ackman didn't hold back his enthusiasm. "It was a quick, well-written, and fascinating read… Definitely worth a read," he posted. What seemed to resonate most with Ackman was the book's straightforward approach to depicting both Karp and his company, an unusual quality in the often-sanitized world of executive biographies.

But Ackman went further than just praising the writing. "I am a Karp fan. We need more high-profile people who are unafraid of speaking freely about important issues," he added, signaling his admiration for Karp's outspoken style in an era when many executives stick to carefully vetted talking points.

From Philosophy Student To Surveillance Tech Billionaire

Karp's journey to becoming a tech billionaire worth $15.3 billion (according to the Bloomberg Billionaire Index) is anything but conventional. Born in New York in 1967 and raised near Philadelphia in a socially active household, he collected degrees from Haverford College, Stanford Law School and Germany's Goethe University along the way.

In 2003, he co-founded Palantir with Peter Thiel and several Stanford technologists. The company's data-analysis platforms got their start with funding from In-Q-Tel, the CIA's venture arm, and became essential tools across U.S. intelligence and military agencies in the post-9/11 era.

Steinberger's book presents Karp as an unconventional leader shaped by vulnerability, extreme discipline and a permanent outsider's perspective.

Fear, Fitness And An Eccentric Lifestyle

"Fear is something that really drives him," journalist Steinberger told The Guardian. The biography paints a picture of a fitness-obsessed, intensely private executive who leads a nomadic lifestyle, practices tai chi and cross-country skiing, and maintains an unconventional personal life.

These quirks aren't performative, Steinberger argues. They're fundamental to how Karp operates Palantir, reflecting a leadership style that's as unusual as it is effective.

The Company Keeps Delivering

Earlier this month, Palantir reported third-quarter revenue of $1.18 billion, beating analyst expectations of $1.09 billion. The AI software company also delivered adjusted earnings of 21 cents per share, surpassing the 17 cents analysts had projected.

Investors have taken notice. Palantir shares have climbed 105.94% year to date, reaching $154.85 as of Friday. That kind of performance has helped the stock rank in the 95th percentile for Growth and the 94th percentile for Momentum among tracked companies.