Cerebras Systems is set to be the largest IPO of 2026 so far, with the AI chipmaker on track to raise up to $4.8 billion at a $48.8 billion valuation after its order book closed roughly 20 times oversubscribed.

The Sunnyvale company lifted its price range to $150 to $160 per share from $115 to $125 and bumped the offering to 30 million shares. At the high end, the deal would be the largest US listing in nearly five years.

Cerebras designs specialized AI chips built around its Wafer Scale Engine, a processor the size of a dinner plate that packs more than 4 trillion transistors onto a single piece of silicon.

The company is focused on inference, the computing required to run trained AI models, rather than training. The pitch is faster and cheaper inference performance than Nvidia ( NVDA ) GPUs, which still dominate both sides of the market.

OpenAI’s Circular Playbook

A March Amazon Web Services partnership and OpenAI’s $20 billion-plus compute deal largely solved the customer concentration problem that derailed Cerebras’ 2024 listing attempt. But access to Sam Altman’s inner circle did not come cheap.

Cerebras is handing OpenAI warrants worth up to 10% of the company, around $5 billion at the IPO midpoint, or roughly half the gross profit it stands to make on the deal, according to Financial Times calculations.

It is the same playbook OpenAI ran with Advanced Micro Devices ( AMD ) , whose shares have tripled since the two companies announced their own circular arrangement last October.

What Polymarket Traders Are Pricing In

A Polymarket contract on Cerebras’ closing market cap on day one has the $50 billion to $60 billion bucket as the favorite at 33%, followed by $60 billion to $70 billion at 25% and $70 billion to $80 billion at 17%. The “under $50 billion” outcome sits at just 6%.

The Hiive secondary market backs that read, with Cerebras shares reportedly changing hands at $187.53 on Monday, about 17% above the top of the offering range.

The crown may be short-lived. SpaceX, OpenAI and Anthropic are all reportedly preparing 2026 listings, with SpaceX and OpenAI alone expected to raise a combined $135 billion. Polymarket currently has SpaceX at 87% to finish 2026 as the largest IPO by market cap.

Cerebras begins trading on the Nasdaq under the ticker CBRS on Thursday.

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