A trial pitting two founders of OpenAI - Sam Altman and Elon Musk - against each other has opened in California, with the sides presenting duelling narratives about the company's history and obligations to consumers. Musk, wearing a dark suit and tie, was asked by one of his lawyers what the lawsuit was about when he took the stand. It's actually very simple, he said. It's not okay to steal a charity... If it's okay to loot a charity, the entire foundation of charitable giving will be destroyed.

OpenAI is racing to catch up to its greatest rival. OpenAI does not like to be left out. The week after Anthropic announced Claude Mythos Preview --an AI model that has put governments around the world on edge because of its potential ability to hack into banks, energy grids, and military systems--OpenAI shared a program that is uncannily similar. And just like Anthropic did with its model, OpenAI has, for cybersecurity purposes, restricted access to this new bot, called GPT-5.4-Cyber, to a small group of trusted users. This sequence has become something of a pattern: First Anthropic will make an announcement, and then OpenAI will follow suit.

Plus: OpenAI has ended its exclusive partnership with Microsoft. Elon Musk and Sam Altman are going to court over OpenAI's future Ahead of OpenAI's IPO, the court could rule on whether the company can exist as a for-profit enterprise. It could even oust its leadership. Musk, an OpenAI co-founder, claims he was deceived into bankrolling the firm under false pretenses. Find out how the trial could upend the global AI race . In a celebrated episode, a community of gnomes sneak out at night to steal underpants.

The bitter feud between Elon Musk and OpenAI boss Sam Altman has raged for years, but has mostly played out online in the form of accusations, counter-accusations and jibes. But starting on Tuesday, the beef between the two tech billionaires will shift to a much higher-profile forum: a federal courtroom in California, where their row will be the focus of a month-long trial. Being considered is Musk's claim that Altman - with whom he founded OpenAI - has swindled him out of millions of dollars and reneged on the ChatGPT-maker's original non-profit mission. Musk and Altman themselves will be among those to testify in a case in which the future of AI could be at stake. And while one will presumably emerge the winner, it's plausible that neither will emerge from the saga unscathed.

Evaluating generative AI models is increasingly resource-intensive due to slow inference, expensive raters, and a rapidly growing landscape of models and benchmarks. We propose ProEval, a proactive evaluation framework that leverages transfer learning to efficiently estimate performance and identify failure cases. ProEval employs pre-trained Gaussian Processes (GPs) as surrogates for the performance score function, mapping model inputs to metrics such as the severity of errors or safety violations. By framing performance estimation as Bayesian quadrature (BQ) and failure discovery as superlevel set sampling, we develop uncertainty-aware decision strategies that actively select or synthesize highly informative inputs for testing. Theoretically, we prove that our pre-trained GP-based BQ estimator is unbiased and bounded. Empirically, extensive experiments on reasoning, safety alignment, and classification benchmarks demonstrate that ProEval is significantly more efficient than competitive baselines. It requires 8-65x fewer samples to achieve estimates within 1% of the ground truth, while simultaneously revealing more diverse failure cases under a stricter evaluation budget.

Elon Musk and Sam Altman are going to court over OpenAI's future Elon Musk says he's suing to save the company's mission. The case could have huge consequences for OpenAI and the AI race. After a yearslong legal feud, Elon Musk and OpenAI CEO Sam Altman are heading to trial this week in Northern California in a case that could have sweeping consequences. Ahead of OpenAI's highly anticipated IPO, the court could rule on whether the company is allowed to exist as a for-profit enterprise and might even oust its current executive leadership, including Altman. Musk is suing OpenAI, alleging that Altman and OpenAI president Greg Brockman deceived him into bankrolling the company in its early days by promising to maintain it as a nonprofit dedicated to developing AI that benefits humanity, only to later restructure the company to operate a for-profit subsidiary. Musk cofounded OpenAI with Altman and others in 2015, but he left in 2018 after a bitter power struggle.

Elon Musk Boosts New Yorker's Sam Altman Exposé on X as Trial Begins The move comes as the trial for Elon Musk's lawsuit against OpenAI kicks off in federal court in Oakland. Elon Musk is boosting a post on X promoting The New Yorker's extensive investigation into Sam Altman's allegedly deceptive behavior, WIRED has confirmed. The move comes just as Musk's lawsuit against OpenAI and Altman heads to a jury trial in a federal courtroom on Monday morning. People scrolling X on Monday reported seeing an April 6 post from Ronan Farrow, a coauthor on the New Yorker article, promoting the investigation. A pop-up on the post on X's mobile app says it was boosted by @elonmusk, who also owns the platform.

PCWorld reports that OpenAI has launched GPT-5.5, its most advanced AI model, exclusively for paying ChatGPT subscribers on Plus, Pro, Business, and Enterprise plans. The new model delivers faster, more efficient performance in coding, research, and math while outperforming competitors like Google's Gemini 3.1 Pro and Anthropic's Claude Opus 4.7. GPT-5.5 represents a significant step toward OpenAI's'super app' vision, integrating various AI services into one comprehensive platform. OpenAI recently launched GPT-5.5, which the company describes as its most advanced and intuitive AI model to date. The new model is said to be both faster and more efficient, with specific improvements in areas including coding, research, and math. At the same time, it's said to perform better compared to competing models like Google's Gemini 3.1 Pro and Anthropic's Claude Opus 4.7. According to OpenAI co-founder Greg Brockman, GPT-5.5 is also a step towards the company's vision of a future "super app," where services such as ChatGPT, Codex, and an AI-driven web browser are integrated into a single platform, reports TechCrunch . GPT-5.5 is currently rolling out to paying ChatGPT users, which includes those on Plus, Pro, Business, and Enterprise plans. This article originally appeared on our sister publication PC för Alla and was translated and localized from Swedish.

The two companies announced an amended partnership that lets OpenAI use other cloud platforms and offer its models to other companies. OpenAI is opening up its partnership with Microsoft in the latest amendment to the major multi-year collaboration between the tech giants. The latest changes allow OpenAI to offer its latest AI models to other companies and through other cloud providers, stripping Microsoft of its exclusivity rights. In a joint announcement posted on OpenAI and Microsoft's websites, Microsoft will still be OpenAI's primary cloud partner with the latest products shipping first on Azure, but OpenAI is now allowed to use any cloud provider. Sam Altman, OpenAI's CEO, posted on X that the company is now able to make our products and services available across all clouds.

A recent attack on Sam Altman's home and OpenAI offices has put corporate security under renewed scrutiny. Records reveal how much some tech firms spend to arm up. Elon Musk called violent crime in San Francisco " horrific " and moved the offices of his social media business X outside the city in 2024 because of safety and business considerations. Other local tech companies have attempted to address their security concerns by partnering directly with cops. Airbnb and Salesforce are among businesses that for years have contracted San Francisco police to protect their offices on a regular basis, according to public records obtained by WIRED.