Cerebras stock hits post-IPO low, tumbling 20% for the week on Nvidia pressure and lockup expiration

Cerebras Systems Inc. signage during the company's initial public offering (IPO) at the Nasdaq MarketSite in New York, US, on Thursday, May 14, 2026.

Michael Nagle | Bloomberg | Getty Images

Cerebras stock plummeted nearly 20% this week to its lowest price since the company's monster IPO in May, after a report that chip giant Nvidia will power a crucial piece of OpenAI's latest model.

Research firm SemiAnalysis posted on X on Wednesday that OpenAI will power its "Ultrafast" mode for GPT-6.1 Sol with Nvidia graphics processing units instead of Cerebras hardware. Cerebras shares are now down by more than half since their initial pop that followed the company's debut on the Nasdaq.

The stock, which closed on Friday at $166.43, was also under pressure this week due to the expiration of post-IPO restrictions on some insider shares.

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Cerebras' stock price

It's a significant fall from grace for Cerebras, which closed at a $95 billion market cap on the first day of trading, just shy of joining the ranks of Meta, Alibaba and now SpaceX, which closed their initial day with valuations over $100 billion.

Cerebras' market cap now sits at just over $39 billion.

Investors were excited by the prospect of an alternative to Nvidia to power AI. Cerebras makes dinner plate-sized ASICs, or a custom microchip built for inference workloads, and leases them from inside its own data centers as a cloud service. In January, Cerebras struck a deal worth over $10 billion with OpenAI to supply it with 750 megawatts of computing power through 2028.

Losing OpenAI inference to Nvidia has put a damper on that exuberance. According to McKinsey, inference is set to surpass training as the most dominant workload in AI data centers by the end of the decade.

Prior to that, up to 14.6 million shares have been unlocked for sale every two weeks since Aug. 19.

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