Cerebras IPO debuts at $66 billion + OpenAI weighs Apple breach claim

Cerebras Systems priced its IPO at $185 per share — above its $115 to $160 range — and raised roughly $5.5 billion before the stock more than doubled on debut Thursday, closing at $311 for a $66 billion market cap. The S-1 names OpenAI, Group 42, Saudi Arabia's MBZUAI, and Amazon Web Services as top customers, and Cerebras swung to profitability on $510 million of 2025 revenue. The pop validates the thesis that frontier labs will pay a premium for Nvidia alternatives if inference economics work — and gives Cerebras a public-market currency to chase Nvidia's data-center share more aggressively.

Bloomberg reports OpenAI has hired outside counsel to explore legal options against Apple, citing frustration that the ChatGPT integration in Siri and Visual Intelligence — announced at Apple's June 2024 developer conference — has delivered far fewer paying ChatGPT subscribers than projected, and that the feature has been buried in iOS surfaces. Sources familiar with the matter say a formal breach-of-contract notice is on the table but unlikely to be filed before OpenAI's ongoing federal trial with Elon Musk concludes. Neither company has publicly acknowledged the dispute. If filed, it would be among the first frontier lab lawsuits against a Big Tech distribution partner — a meaningful shift in the bargaining dynamic between labs and the operating systems they ship inside.

OpenAI made Codex available inside the ChatGPT mobile app on Thursday in preview, with rollout across iOS and Android on every subscription tier including Free. Mobile Codex is scoped to remote workflow management — review outputs, approve commands, change models, switch threads, kick off new tasks — rather than the autonomous background execution the desktop CLI added last month. The change makes Codex meaningfully more ambient: engineers reviewing diffs on a phone is a different work pattern than reviewing them on a laptop, and free-tier availability lowers the bar for adoption beyond OpenAI's ChatGPT-paying base.

Anthropic announced a four-year, $200 million commitment to the Gates Foundation, structured as a mix of cash grants, Claude usage credits, and technical support from its Beneficial Deployments team. Focus areas span global health (polio, HPV, and preeclampsia and eclampsia among named disease targets), life sciences, education, and economic mobility, with regional emphasis on sub-Saharan Africa, India, and other low- and middle-income countries. Launch partners include the Institute for Disease Modeling and the Global AI for Learning Alliance. It is the largest single philanthropic commitment from a frontier lab to date and a meaningful structural signal that Anthropic intends to be measured by social-impact deployments alongside its commercial book.

Anthropic published its Claude for Legal plugin suite on GitHub under the Apache 2.0 license, two days after announcing the proprietary plugin launch. The repo includes twelve practice-area plugins (commercial, corporate, employment, privacy, regulatory, IP, litigation, plus a law-student bundle), domain-skill markdown files, scheduled-agent templates for docket and renewal watchers, and MCP connectors for Ironclad, DocuSign, iManage, Everlaw, CourtListener, and Box. Stars passed 4,800 within roughly twenty-four hours — a strong signal that in-house counsel and legal-tech vendors view the reference implementation as a forking starting point rather than as locked-in vendor IP.

Amazon Science published Promptimus, a four-step iteration framework that identifies failure points in existing high-quality prompts via metric analysis and generates targeted refinements — either full rewrites in "standard mode" or surgical edits in "edit mode" for complex enterprise prompts. On a 20-benchmark evaluation spanning reasoning, math, QA, and coding, Promptimus posts an average score of 0.792 versus 0.765 for the strongest of six leading baselines and wins on 16 of the 20 benchmarks; enterprise-task gains range from 3.18% to 90.27%. The framework will be made available through Amazon Bedrock, positioning AWS to compete in the increasingly crowded prompt-optimization tooling category against DSPy, OpenAI's optimizer, and Anthropic's prompt improver.