Cerebras Slipped Below Its IPO Price Just as Insiders Filed to Sell
Cerebras stock slipped below its IPO price on the same day insiders filed to sell and a report surfaced questioning whether its anchor customer moved its fastest model to rival hardware.
This post may contain links from our sponsors and affiliates, and Flywheel Publishing may receive compensation for actions taken through them.
Cerebras Systems (NASDAQ:CBRS) last traded at $177.65, down 8.87% from a $194.95 prior close. That puts the stock under its $185 IPO offer price.
The shares opened their first day of trading at $350, so early public buyers have lost most of that premium. From the May 14, 2026 close of $311.07, the stock is down 42.89%.
Three separate events landed on September 30, 2026. The post-IPO lockup ended, two senior officers filed notices of planned sales, and a secondhand report questioned whether OpenAI’s newest fast model runs on Cerebras hardware.
For a company whose IPO pitch leaned on OpenAI, that deserves examination.
What Expired, What Was Filed and What Was Only Reported
A lockup bars insiders and early holders from selling for a set period after an IPO. When it ended at 6 a.m. Eastern, about 19.4 million shares became eligible for sale.
Officers also filed Form 144 notices covering about $84.3 million of stock. A Form 144 records an intent to sell; only a later Form 4 confirms an executed sale.
The third item is a SemiAnalysis claim that OpenAI’s newest ultrafast model runs on standard GPUs instead of Cerebras systems. OpenAI had previously confirmed that an earlier ultrafast model ran on Cerebras hardware.
Sizing the Insider Filings Against Cerebras
Chief Operating Officer Dhiraj Mallick filed to sell 396,000 shares worth about $77.9 million. Chief Financial Officer Robert Patrick Komin Jr. filed to sell 32,500 shares worth about $6.39 million.
Most of Mallick’s shares come from options and performance-based stock awards. Against 112,247,000 shares outstanding, these notices are small next to the unlocked block.
The business underlying is growing. Second-quarter core revenue rose 103% to $209.9 million, and remaining performance obligations, meaning contracted revenue not yet recognized, reached $25.4 billion.
Why the Hardware Report Carries the Bigger Risk
Insiders commonly sell when a lockup ends. The notices also leave out whether, when, or at what price any shares were actually sold.
The hardware claim cuts closer to the IPO story. OpenAI signed a multi-year deal for 750 MW of inference compute worth more than $20 billion, and CEO Andrew Feldman said on the August 12 call that OpenAI will “stay a big part next year.”
If OpenAI sends its fastest models elsewhere, that concentration becomes a liability. At 68x trailing sales, the stock has little room for doubt about its anchor customer. We reverse-engineered the characteristics earlier chip winners shared before their biggest runs in a free playbook on spotting the next Nvidia, and customer concentration is one signal worth watching.
How the Valuation Leaves CBRS Exposed to Customer Doubt
The risk outweighs the reward until the picture clears. The growth is real, but a stock at 217x forward earnings needs its largest customer relationship to be secure, and right now it is questioned.
Analysts remain upbeat, with 3 strong buy and 7 buy ratings and an average target of $291.64. That optimism rests on the same OpenAI ramp now in doubt.
Form 4 filings will show whether Mallick and Komin actually sold and at what price. A direct statement from OpenAI or Cerebras on which hardware runs the new model would settle the report.
A close back above $185 alongside third-quarter core revenue inside the $214-$216 million guidance range would suggest the selloff came from lockup supply and would ease that risk.
Contact [email protected] for any questions or corrections.
Omor Ibne Ehsan is a writer at 24/7 Wall St. He is a self-taught investor with a focus on growth, cyclical, and dividend equities that have strong fundamentals, value, and long-term potential. He also has an interest in high-risk, high-reward investments such as penny stocks.
