Cerebras Shares Jump 6.3% After Altman Calls Chipmaker a 'Close Partner'

Cerebras Systems stock rose 6.3% in premarket trading on Monday, Oct. 5, 2026, to $177 per share after OpenAI CEO Sam Altman publicly called the AI chipmaker a "close partner," pushing back on speculation about the two companies' relationship. Altman wrote on X on Friday that the companies have "a deep engagement pushing on the frontiers of speed." The rebound follows a 20% weekly decline that took Cerebras to its weakest level since its Nasdaq listing, after reports that OpenAI selected Nvidia GPUs — not Cerebras chips — to power the "Ultrafast" mode in GPT-6.1 Sol. Cerebras' market cap has fallen to just over $39 billion from $95 billion at its May debut. The company holds a $10 billion OpenAI agreement, struck in January, to deliver 750 megawatts of computing capacity through 2028. Citi analysts said Friday their revenue projections through 2028 are unchanged, adding that a sustained recovery depends on signs gross margins are bottoming.