In May 2026, Cerebras Systems pulled off one of the flashiest market debuts of the year. Five months later, the AI chip designer's stock changes hands below the price institutional buyers paid before the opening bell — a reversal that has come despite financials showing steep revenue growth and a swing to profitability.

The company set the price of its initial public offering at $185 per share on May 13, 2026, selling 30 million shares and raising $5.55 billion in the process. The deal gave Cerebras a fully diluted valuation of approximately $56.43 billion and made the listing the largest US technology IPO of the year up to that point.

By early October 2026, shares were changing hands between $164 and $177, with the stock recently sitting around $165. That is roughly $20 below the offer price — and a long way down from the $350 opening print. Early buyers who chased the debut are now holding something worth less than half that figure. Because the offer price was fixed before trading began, the gap below it doubles as a running measure of how far public-market sentiment has drifted from the price institutions agreed to pay in May.

From a 68% First-Day Pop to Underwater

Trading under the ticker CBRS on Nasdaq, the stock opened at $350 and finished its first session at $311, a 68% gain over the offer price. It has since given back the entire first-day premium and then some.

Timing played a part in the slide. The company's lockup period expired on October 1, 2026, and insider sales worth approximately $84 million lined up with that date. Lockups are the standard post-IPO windows during which insiders are barred from selling, so an expiry can put newly eligible shares on the market all at once — a mechanism investors in freshly listed companies tend to watch closely.

The Numbers Behind the Hype

Cerebras reported 2025 revenue of $510 million, up 76% from $290.3 million in 2024. The bottom line moved even more dramatically: net income reached $237.8 million in 2025, compared with a loss of roughly $482 million the year before. Measured against that 2025 revenue, the roughly $56.43 billion IPO valuation equated to about 110 times trailing sales — a level that builds in expectations of continued rapid growth.

The company holds a multi-year inference capacity agreement with OpenAI and has partnerships with AWS. Its signature product is the wafer-scale engine. While most chipmakers slice a silicon wafer into many small chips, Cerebras instead builds one enormous processor across the wafer itself.

The Nvidia Comparison, and Its Limits

The Motley Fool framed the story with a pointed comparison, noting that Cerebras is about as big today as Nvidia's data center business was nearly a decade ago, while arguing that the similarities mostly end there.

Cerebras faces two widely cited concerns. One is customer concentration, meaning a meaningful share of business can depend on a small number of large buyers. The other is Nvidia itself. Concentration cuts both ways: a deal with a name like OpenAI is a powerful endorsement, but any shift in a major customer's spending plans can hit the top line hard.

What to Watch From Here

Several things are worth monitoring. The next earnings reports will show whether the growth rate seen in 2025 holds up now that Cerebras operates as a public company. Insider selling is another signal to track now that the lockup has lifted — continued heavy sales could weigh on sentiment, while restraint might help steady the shares. Any fresh detail on the scale or duration of the OpenAI agreement would also speak to the customer-concentration question that hangs over the growth story.