How Situational Awareness’s Leopold Aschenbrenner Lost $30 Billion Just Before His Wedding to Anthropic’s Avital Balwit

Twenty-four-year-old AI wunderkind Leopold Aschenbrenner faced an unenviable situation in the days before his wedding to his fiancée, Anthropic chief of staff Avital Balwit: to sell roughly $3.5 billion worth of the private Anthropic stake held by Situational Awareness, his AI-centric $45 billion hedge fund, to stave off a margin call.

Aschenbrenner, a German national, graduated as valedictorian at just 19 from Columbia University, where he cofounded an effective-altruism club (the movement, now quite intertwined with AI, that says one should rely on data to prioritize causes that will have the greatest positive impact on others). He then went on to cut his teeth at fellow EA follower Sam Bankman-Fried’s FTX. It was there that he met recent Rhodes scholar Balwit. After FTX collapsed and Bankman-Fried was arrested on charges of orchestrating an $8 billion fraud, their careers diverged into the AI arms race. (Bankman-Fried was later convicted of charges including fraud and conspiracy to commit fraud.) Aschenbrenner joined Sam Altman’s OpenAI, working on the company’s superalignment team, while Balwit landed at Dario Amodei’s Anthropic, where she became Amodei’s chief of staff.

Aschenbrenner’s tenure at OpenAI lasted a little over a year. In April 2024, he was fired after allegedly sharing sensitive internal information with, according to The Wall Street Journal, Holden Karnofsky, whose wife works at Anthropic. (Aschenbrenner has said that the alleged leak involved a document he had reviewed for sensitive information and that it was “totally normal” to share this kind of information with external researchers for feedback.)

Two months later, he published the 165-page essay “Situational Awareness,” which quickly became required reading in Silicon Valley. In it, he argued that artificial general intelligence would arrive much sooner than most investors expected, and that the real winners would not be consumer AI applications but the unglamorous pieces of infrastructure powering them: chips, memory, data centers, electricity, cooling, and networking. Software, by contrast, would become commoditized.

By the end of 2024, at just 22 years old, he had launched a hedge fund named after the essay. That November, the firm raised $100 million, according to The New York Times. The thesis proved so profitable that by the end of May 2026, the San Francisco–based fund was reportedly up more than 1,000% after fees since its inception. Situational Awareness quickly attained cult status. Rival hedge funds and even retail traders began mimicking Aschenbrenner’s trades, piling up stocks after he bought them and dumping positions after he sold.

But returns like that rarely come without extraordinary risk. According to CNBC, the fund operated with up to four times leverage, leaving little margin for error.

Then the market turned.

Because the portfolio was financed with heavy leverage, relatively modest declines began triggering margin calls from lenders.

According to The Wall Street Journal, Aschenbrenner agreed to sell approximately $3.5 billion of the firm’s Anthropic stake to a consortium of venture capital investors last Wednesday before reversing course. Instead, according to the Journal, Ken Griffin’s Citadel agreed to purchase the bulk of the fund’s public equity portfolio, providing an alternative source of liquidity.

All of this unfolded just days before Aschenbrenner and Balwit were scheduled to marry in picturesque Carmel-by-the-Sea, surrounded by Silicon Valley heavy hitters, many of whom were also Aschenbrenner’s investors. It was, by all accounts, a quintessential Bay Area wedding, complete with breakout rooms for social networking (the prompt was supposed to be investment ideas and trends, but given the events of the prior week, the couple opted for conversations about life and philosophy instead of discussions of finance). The event took place at a private, Tuscan-inspired estate overlooking the ocean, and after the ceremony, the 80 to 100 guests sipped on Napa Valley’s finest wine, with the DJ playing a Berghain-style set inspired by Aschenbrenner’s German roots—all of this happened in time for guests to have returned home and gotten into bed by 11 p.m. Amodei reportedly did not attend.

One person with knowledge of the wedding underscored that “it wasn’t like Aschenbrenner went broke and couldn’t pay for the venue or the caterer.” While Situational Awareness’s loss of over $30 billion was a bit of an elephant in the room, Aschenbrenner was still a 24-year-old multibillionaire.