Investors are overexcited about AI, says OpenAI CEO Sam Altman

OpenAI CEO Sam Altman has warned that the current wave of investment pouring into artificial intelligence could fuel a bubble similar to the dot-com crash of the late 1990s and early 2000s. Speaking at recent events and in media interviews, Altman compared the frenzy around AI startups to the irrational exuberance that once surrounded internet companies.

“Are we in a phase where investors as a whole are overexcited about AI? My opinion is yes,” Altman said, adding that while the underlying technology is transformative, the hype and extreme valuations could leave many companies exposed. He cautioned that some AI startups are raising hundreds of millions of dollars with little more than an idea, and that “insane” valuations would not guarantee long-term success.

Data reflects the scale of this surge. According to PitchBook, AI startups in the United States raised $104.3 billion in the first half of 2025 alone, almost equalling the total raised by all startups in 2024. Nearly two-thirds of venture funding this year has gone to AI companies, compared with 49% last year.

Altman urged both entrepreneurs and investors to focus on fundamentals rather than momentum, warning that companies with weak business models are likely to fail when the market corrects. “Smart people get overexcited about a kernel of truth,” he noted.

Despite concerns over overheating, OpenAI itself continues to expand aggressively. The company raised $40 billion in March in the largest private tech funding round to date, securing a valuation of $300 billion. Its flagship product, ChatGPT, now attracts around 700 million weekly users, a fourfold increase compared with last year, making it the fifth most-visited website globally. Altman said the platform is on track to overtake Facebook and Instagram to reach the third spot, behind only Google and YouTube.

To support this growth, OpenAI plans to invest trillions of dollars in computing infrastructure and datacentre construction in the coming years. Altman acknowledged that some economists might view this strategy as “crazy” or “reckless,” but insisted the company is pressing ahead. He also revealed that OpenAI is developing a novel financial instrument to fund these large-scale ambitions.

Looking ahead, Altman said an eventual stock market listing is likely. “I do think we have to go public someday, probably,” he said, while conceding that he may not be the ideal person to lead OpenAI as a public company.

The comments underline a tension in the AI sector: while the technology continues to grow at an unprecedented pace, many fear that the rush of capital is unsustainable. For Altman, the challenge lies in balancing rapid expansion with the discipline to avoid repeating the mistakes of past technology booms.