Leopold Aschenbrenner's hedge fund — grown from $225 million to $20 billion on AI/chip trades — got margin called during the chip-stock crash and was forced to sell his entire public portfolio, reportedly bought by Citadel, because his leverage amplified the losses.
Breaking news to open the show: the Philadelphia Semiconductor Index is down over 20% in a month (Samsung -38%, KOSPI -40%+), and 25-year-old Leopold Aschenbrenner, who left OpenAI to run a fund he grew 100x to $20 billion, was margin-called on Thursday and had to sell his entire public portfolio — reportedly bought by Citadel's Ken Griffin. ✦ AI generated
Jason Calacanis · All-In Podcast · 2026-07-31 · original ↗
starts at this moment · 1:12
All right, everybody. We got to talk about chip stocks crashing after an alltime runup. And we had a major hedge fund get margin called and some incredible margin calls happening in South Korea. Leopold Ashen Brener is a 25-year-old hedge fund manager. He left OpenAI two years ago to start his own fund and apparently according to reports, this is breaking news on Thursday when we tape, he got margin called and had to sell his entire public portfolio to cover massive losses caused by his leverage. And who bought them? none other than Citadel's Ken Griffin. We don't know if it was Ken Griffin himself, but Citadel bought it according to the early reports. Leopold had insane returns and he rode the wave of AI and chips and Frontier Labs as recently as this month. Uh, and he started the fund with $225 million in 2024. He grew it 100x to 20 billion this year or so. Ran it all the way up to 45 billion. According to our friends at CNBC at the end of the June, he was reportedly up 4x450% this year. Uh some have reported that he's also selling his massive anthropic stake to cover these losses, but the Wall Street Journal is disputing it. Again, uh he we're we're happy to have him here on the program. How did this all blow up? Well, NASDAQ's chip index, this is called the Philadelphia Semiconductor Index, is down over 20% over the last month. That's bare market territory. Obviously, definition of bare market territory for those of you who don't play in the markets is anything over 20%. Uh the index included the top 30 US listed chips. That's people like Nvidia, TSMC, AMD, Micron, you know, all those big names. But the index bounced back a bit today, up 7% when we're taping. So, we may have found a bottom. Unfortunately for Leopold, he had already sold. Samsung and SKH, two South Korean chip companies that are not included in the NASDAQ index, also got smashed, crushed, demolished. Samsung down 38% over last month. SKH Highix down 14% since going public 3 weeks ago. The Cosby, that's South Korea's version of the S&P 500, is down over 40% in the last 40 days. Between last Friday and Wednesday, leading chip companies shed over a trillion dollars in market cap combined. So to put this in context, chip stocks had a legendary run the past couple of years, but uh you know trading on leverage, we'll talk about it. Very dangerous. If there's a downturn, we'll get into the South Korea wrinkle as well. Even with this downturn, the 5-year results are still spectacular. Jimoth Micron up 850% mostly in the last year. Nvidia up 875% in the last 5 years and Broadcom up 663%. Let's discuss it.
verbatim transcript · starts at 1:12
1:12if you name your fund situational awareness, that's >> Yeah. Come on the pot anytime, Lualt. All right, everybody. We got to talk about chip stocks crashing after an alltime runup. And we had a major hedge fund get margin called and some incredible margin calls happening in South Korea. Leopold Ashen Brener is a 25-year-old hedge fund manager. He left OpenAI two years ago to start his own fund and apparently according to
1:40reports, this is breaking news on Thursday when we tape, he got margin called and had to sell his entire public portfolio to cover massive losses caused by his leverage. And who bought them? none other than Citadel's Ken Griffin. We don't know if it was Ken Griffin himself, but Citadel bought it according to the early reports. Leopold had insane returns and he rode the wave of AI and
2:03chips and Frontier Labs as recently as this month. Uh, and he started the fund with $225 million in 2024. He grew it 100x to 20 billion this year or so. Ran it all the way up to 45 billion. Now he's at 200x earlier this month by trading on leverage. According to our friends at CNBC at the end of the June, he was reportedly up 4x450% this year. Uh some have reported that
2:33he's also selling his massive anthropic stake to cover these losses, but the Wall Street Journal is disputing it. Again, uh he we're we're happy to have him here on the program. How did this all blow up? Well, NASDAQ's chip index, this is called the Philadelphia Semiconductor Index, is down over 20% over the last month. That's bare market territory. Obviously, definition of bare market territory for those of you who
2:55don't play in the markets is anything over 20%. Uh the index included the top 30 US listed chips. That's people like Nvidia, TSMC, AMD, Micron, you know, all those big names. But the index bounced back a bit today, up 7% when we're taping. So, we may have found a bottom. Unfortunately for Leopold, he had already sold. Samsung and SKH, two South Korean chip companies that are not
3:19included in the NASDAQ index, also got smashed, crushed, demolished. Samsung down 38% over last month. SKH Highix down 14% since going public 3 weeks ago. The Cosby, that's South Korea's version of the S&P 500, is down over 40% in the last 40 days. Between last Friday and Wednesday, leading chip companies shed over a trillion dollars in market cap combined. So to put this in context, chip stocks had a legendary run the past
3:48couple of years, but uh you know trading on leverage, we'll talk about it. Very dangerous. If there's a downturn, we'll get into the South Korea wrinkle as well. Even with this downturn, the 5-year results are still spectacular. Jimoth Micron up 850% mostly in the last year. Nvidia up 875% in the last 5 years and Broadcom up 663%. Let's discuss it. >> If I was going to give you one piece of
4:16advice when you're running risk is you have to manage leverage incredibly carefully because when it runs ahead of you, the unwind is incredibly violent and it's incredibly quick. That's the biggest problem with with running either massively levered long or massively levered short. So I don't know to what extent he was running lever but the rumors are he was running like three and a half turns which just to give you a