Cerebras Systems closed at $146.62 on Monday, down 10.69% and hitting its lowest close since its IPO. Shares traded as low as $145.75, with volume reaching about 18.1 million shares, more than double the recent one-month average of roughly 8.3 million. The stock is now 20.7% below its $185 IPO price, 52.9% below its first-day close of $311.07, and 62.0% below the $386.34 intraday high set on its debut.
The slide comes ahead of a scheduled lockup release. Up to 19.4 million Class A shares become eligible for sale on October 14, with another tranche of approximately 19.4 million shares set for October 28. A similar unlock occurred on September 30. Insiders sold $387.7 million of stock in the past quarter, including $25.1 million by CTO Sean Lie and $10.5 million by director Steven Vassallo.
Pressure also stems from a report that OpenAI's GPT-6.1 Sol "Ultrafast" inference tier runs on Nvidia GPUs rather than Cerebras hardware. Neither OpenAI nor Cerebras confirmed the claim, but OpenAI CEO Sam Altman described Cerebras as a close partner with deep engagement around speed. The broader OpenAI-Cerebras agreement includes a phased deployment of 750 megawatts of low-latency inference capacity through 2028. Cerebras disclosed $25.4 billion of remaining performance obligations as of June, with a significant share tied to OpenAI, making customer concentration a key concern.
Microsoft added to the competitive pressure by saying its Maia chips will become the primary inference system for its own products and services starting in 2027. Analyst price targets remain above the stock price, with an average 12-month target of $299.90. Ratings are still mostly positive: two Strong Buy, ten Buy, one Hold, and one Sell. Citigroup lowered its target from $340 to $320, and Mizuho from $310 to $300.
The next earnings report is not yet company-confirmed, with third-party calendars pointing to November 10, 11, or 19. Cerebras guided third-quarter core revenue to approximately $214 million to $216 million and a core gross margin of 38% to 40%.
