OpenAI Acquired 4.2% of Cerebras for Just $100 Weeks Before Launching 'Ultrafast'

In July, OpenAI exercised warrants to acquire a 4.22% stake in Cerebras. The exercise cost was only about $100, but based on Cerebras's stock price as of August 13, the estimated value of this stake is approximately $2.3 billion.

Subsequently, OpenAI unveiled Ultrafast, a new service tier based on GPT-5.6 Sol. Ultrafast utilizes Cerebras's Wafer Scale System (WSS) to generate up to 750 output tokens per second, offering speeds up to 14x faster than the existing Standard tier.

The core of this collaboration lies in securing computing capacity. OpenAI has committed to progressively purchasing 750MW of inference capacity by 2028, with an option to secure an additional 1.25GW by 2030. Cerebras's wafer-sized chips feature 44GB SRAM, keeping model weights on-chip to reduce data movement bottlenecks and maximize speed.