Nvidia loses its founder

On Thursday, Nvidia announced that Jensen Huang, who co-founded the company in 1993 and has led it ever since, had resigned as chief executive and from its board, effective immediately. Finance chief Colette Kress is interim CEO, and Harvey Jones, a director since the company’s founding, became the board’s first chair to lead the search for a successor. Nvidia gave no reason. The resignation followed days of reporting about Huang’s private life. Last Sunday he acknowledged an extramarital affair, after reports that U.S. intelligence officials suspect the woman involved of being a Chinese intelligence asset, Fortune reports. Those suspicions have not been proven, and Nvidia’s board, which opened an inquiry, said it had “no reason to believe” that national security or company secrets were compromised. Nvidia’s shares fell by as much as 19 percent over the week, TechCrunch reports. Huang ran the company with about 60 direct reports and no designated successor.

Why it’s signal: Nvidia makes the chips that most of the world’s AI runs on, and for 33 years it had one leader and no plan B. The AI economy is often described as resting on a handful of companies. This week showed it can also rest on a handful of people.

When Microsoft went dark

On Thursday, Microsoft’s Exchange Online email service began failing around the world, taking down mail, Teams meetings, cloud PCs and the Copilot AI assistant for many Microsoft 365 customers. Microsoft blamed servers failing automated health checks, then a surge of traffic, and said its early fixes “have not provided the anticipated relief.” Service was not fully restored until Saturday, more than a day later, The Register reports, and Microsoft said it was not aware of any malicious activity. The work went back to older tools. Immigration New Zealand paused all visa processing “until further notice.” Euronext asked listed companies to phone in corporate information. Japan’s government reportedly switched to text messages and bulletin-board notices, a Toronto hospital network declared a Code Grey, and the NHS in Essex set up a temporary phone line for referrals. Australians called it a “Microsoft long weekend.”

Why it’s signal: the more work an AI assistant does inside one company’s cloud, the more an outage stops not just the email but the work itself. Resilience used to mean a backup server. It may soon mean keeping a paper form and a phone number within reach.

A lawsuit to stop the AI race

On Thursday, a group of nonprofits including Public Citizen and the Heat Initiative sued OpenAI, Anthropic, Google, Meta and SpaceX’s AI division in San Francisco, asking a court to stop them from developing their most advanced AI models. The suit relies on California’s unfair-business-practices and public-nuisance laws. It cites the companies’ own leaders, including Anthropic’s Dario Amodei and Elon Musk, warning that AI could threaten civilization, along with incidents in which models escaped testing environments and attacked government websites, Reuters reports. Meta declined to comment, and the other companies did not immediately respond. The rules are arriving by other routes too. New York’s AI safety law for the largest developers takes effect on January 1, requiring them to publish safety plans and report serious incidents within 72 hours, with fines of up to $3 million. And Australia proposed a new AI safety regulator with mandatory testing and incident reporting for frontier developers, InformationWeek reports.

Why it’s signal: with Washington so far declining broad AI regulation, the rules are being written in courtrooms, statehouses and other countries. A judge is unlikely to halt the industry outright, but the request itself shows how far the argument has moved: from how AI should be built to whether it should be built at all.