This reaches beyond tech investors, since the AI buildout has underpinned equity markets<\/a> over the past year, so many index funds and retirement accounts hold a slice of it. A bubble is what happens when prices climb far faster than the businesses behind them can justify, until reality catches up. Citadel is a hedge fund, a private firm that invests money for wealthy clients and institutions. <\/p>\n But the fact that it seems like a bubble isn’t that big a deal if you look at the big picture, according to Griffin. “Any radical transformation of our economy is generally intertwined with a bubble,” he said, recalling the internet boom and adding that he wishes he had kept his Amazon stock. <\/p>\n The companies that emerge on the other side of a bubble tend to lead markets for decades, he argued, though he stopped short of predicting a collapse. His own firm is a case study: Griffin said AI agents, software that carries out multistep tasks on its own, cut some high-level Citadel research from weeks to a couple of hours. <\/p>\n Griffin compared GPUs, the graphics chips that many companies use to train and run AI models, to airline seats. Both have a very low marginal cost to run, meaning the extra expense of serving one more customer is tiny, so prices can collapse once supply outstrips demand. <\/p>\n He pointed to the telecom boom around 2000, when companies laid more fiber-optic cable than demand required and communication prices fell. He also doubted that chips five or six years old, which still earn rental rates he called extraordinary, will keep doing so for another five or six years. <\/p>\n Buyers are getting pickier, Griffin said, sorting which jobs justify premium models from OpenAI and Anthropic and which can run on cheaper open-source alternatives, meaning models anyone can download and run on their own computers. Corporate America has been uneven at extracting value from AI, he added, with companies studying their bills from the labs and asking where the productivity is. <\/p>\n Gartner forecasts worldwide AI spending at nearly $1.5 trillion for 2025, counting everything from chips and servers to AI-enabled phones. Nvidia CEO Jensen Huang said at Davos in January that the industry is only “a few hundred billion dollars” into what he called the largest infrastructure buildout<\/a> in human history, with trillions still to build. If customers balk at premium prices, the chip and cloud companies counting on that spending would feel it first. <\/p>\n On July 30, Situational Awareness, a hedge fund founded by former OpenAI researcher Leopold Aschenbrenner, sold most of its public stock portfolio to Citadel at roughly a 10% discount after its value reportedly fell about 67% in July. <\/p>\n