Terrified of AI, Rich From AI: Jaan Tallinn Braces for Billions He Wishes Weren't Coming

In Saturday’s print edition of The Wall Street Journal, Kate Clark profiles a man who occupies perhaps the strangest corner of the modern AI economy: Jaan Tallinn, the Estonian engineer who helped build Skype, has spent fifteen years warning that humanity is “racing to build a technology that could end humanity” — and is now about to make billions of dollars from the initial public offering of Anthropic, the very company he seeded. The headline captures the paradox bluntly: “He’s Completely Terrified of AI—and He’s About to Make Billions Off It.”

From P2P Code to Existential Dread

Tallinn’s path to this moment runs through some of the odder chapters of tech history. He studied theoretical physics at the University of Tartu, writing a 1996 bachelor’s thesis on travelling interstellar distances using warps in spacetime. He then founded the Estonian games studio Bluemoon with schoolmates Ahti Heinla and Priit Kasesalu; after that company nearly went under, the trio built the FastTrack peer-to-peer engine behind Kazaa for Niklas Zennström and Janus Friis. When that P2P technology was repurposed into Skype around 2003, it carried Tallinn’s code into hundreds of millions of machines. He sold his Skype shares in 2005, when eBay bought the company for $2.6 billion.

The sale left him rich and, by his own account, searching for something to do with the money. He found it in a 2007-ish encounter with the writings of Eliezer Yudkowsky on the AI alignment problem. The idea that seized him, as he later put it, was “that we are seeing the end of an era during which the human brain has been the main shaper of the future.” Tallinn became arguably the most consequential private financier of existential-risk research ever: he co-founded the Centre for the Study of Existential Risk (CSER) at the University of Cambridge and the Future of Life Institute (FLI) in Cambridge, Massachusetts, seeded the Machine Intelligence Research Institute, and has been named to TIME’s 100 most influential people in philanthropy for bankrolling AI-safety work.

The $124 Million That Became a Fortune

Alongside the philanthropy came the investments. Tallinn was an early investor and board member in DeepMind before Google acquired it in 2014 for roughly $600 million. But the defining bet came in May 2021, when he led Anthropic’s $124 million Series A at a $623 million post-money valuation — the round that gave the safety-focused lab, founded by former OpenAI researchers, its real start. Investors in that round also included Dustin Moskovitz, Jim McClave and Eric Schmidt.

The math since then has been vertiginous. Anthropic’s most recent private round, a $65 billion Series H led by Altimeter Capital, Dragoneer and Greenoaks, valued the company at $965 billion. Excluding dilution, Tallinn’s Series A position has returned roughly 250x in under five years. And the endpoint may be much larger: the company is expected to begin marketing an IPO in mid-October at the earliest, with bankers telling potential investors the listing could raise up to $100 billion and value Anthropic at around $2 trillion — which would make it one of the largest IPOs ever attempted, landing days before the U.S. midterm elections. One of Anthropic’s earliest investors thus stands to clear billions in the coming months, as the Journal notes.

The Contradiction He Has Never Resolved

What makes Tallinn more than a lucky early check-writer is that he has never papered over the tension. When OpenAI staff quit to found Anthropic in 2021, complaining that their employer wasn’t taking safety seriously enough, Tallinn funded the spinout — and immediately second-guessed himself. “On the one hand, it’s great to have this safety-focused thing,” he told Semafor in 2023. “On the other hand, this is proliferation.” He has praised Anthropic for a stronger safety culture than its rivals, but adds: “that doesn’t change the fact that they’re dealing with dangerous stuff and I’m not sure if they should be. I’m not sure if anyone should be.”

His activism has only sharpened. He signed FLI’s March 2023 open letter calling for a six-month pause on training systems more powerful than GPT-4, the May 2023 Center for AI Safety statement ranking AI extinction risk alongside pandemics and nuclear war, and the October 2025 FLI statement calling for an outright prohibition on superintelligence development until there is broad scientific consensus that it can be built safely. He has also said that he had yet to meet anyone inside AI labs who put the odds of the next-generation training run “blowing up the planet” at less than one percent. He sits as an observer on Anthropic’s board — watching the machine he funded, without the power to stop it.

The Broader Irony

The profile lands at a moment when the entanglement of AI wealth and AI alarm has itself become the story. Critics — most loudly a recent viral thread by researcher Kevin Bass — argue that Anthropic-linked money now flows through philanthropic vehicles into the very evaluators, think tanks and journalism that amplify warnings about Anthropic’s own technology, creating a self-reinforcing “doom machine” that monetizes fear. Defenders reply that safety spending funded by AI winners is simply how infrastructure gets built in every industry. Tallinn’s position is the purest distillation of the debate: a man whose fortune scales with the thing he believes could end the world, who plans to recycle that fortune into trying to prevent exactly that.

There is also a quieter reading of the Journal piece. Tallinn dances hip-hop, lives modestly for a billionaire, and has six children — the personal texture of a man who treats his wealth primarily as ammunition for a cause. Whether the cause can outrun the compounding is the question his own portfolio keeps raising. When Anthropic’s ticker starts trading, the largest single financial beneficiary of the AI boom’s safety-first lab will be the person most determined to slow it down. That is either the best-aligned incentive in the industry or the strangest conflict of interest in its history. Tallinn, characteristically, seems to think it’s both.