OpenAI's GPT-5.6 Is Dropping on Thursday: What's Different About Sol, Terra and Luna

OpenAI will release its GPT-5.6 series of AI models on Thursday, including three variants: Sol, Terra, and Luna. The models feature improved reasoning, cybersecurity, and reduced hallucinations, but their release comes amid new US government oversight requiring voluntary review of frontier AI models. CEO Sam Altman confirmed the launch, marking a shift in the Trump administration's stance on AI regulation.

OpenAI is getting ready to release its next generation of AI models. The GPT-5.6 series, which includes a trio of new models, will be released on Thursday, CEO Sam Altman confirmed in a post https://x.com/sama/status/2074709023807664454 on X Wednesday. The flagship model is called GPT-5.6 Sol. It's meant to handle deep reasoning tasks and manage agents. Terra is the middle, Goldilocks option in terms of capability and cost, while Luna is the quickest and cheapest to run. They are a "meaningful step up in cybersecurity capabilities" but also have advanced safety guardrails, the company wrote https://deploymentsafety.openai.com/gpt-5-6-preview when outlining the model family in June. OpenAI said Sol makes fewer factual errors, or hallucinations, compared to previous OpenAI models. We don't yet know the specific availability of these models, other than all three will be released on Thursday. CNET reached out and did not immediately receive a response from OpenAI. Disclosure: Ziff Davis, CNET's parent company, in 2025 filed a lawsuit against OpenAI, alleging it infringed Ziff Davis copyrights in training and operating its AI systems. While we've known about GPT-5.6 since its announcement on June 26 https://openai.com/index/previewing-gpt-5-6-sol/ , OpenAI has purposefully slow-rolled its release. Like Anthropic's Claude Mythos 5 /tech/services-and-software/anthropic-project-glasswing-claude-mythos-preview/ , the new GPT models are purportedly the most advanced AI available, and because of that, AI companies are being more hesitant with making them public. And for the first time, the US government is holding companies back with new requests for government review of AI models before they can be widely released. On June 2, President Donald Trump issued an executive order https://www.whitehouse.gov/presidential-actions/2026/06/promoting-advanced-artificial-intelligence-innovation-and-security/ requiring the Defense Department to design a system that has AI developers voluntarily sharing access to new frontier models with the government. Government officials have 30 days to review the tech and raise red flags. This is a different legal standard than the one under which the government killed and then resurrected Claude Fable 5 https://www.cnet.com/tech/services-and-software/anthropic-restores-claude-fable-5-government-export-control-news/ . OpenAI said that it had voluntarily given the government and some "trusted partners" early access. It's not clear who these partners are and what their expertise is, and OpenAI declined in June to comment on the specifics, referring CNET to the announcement. A White House official told CNET that the US government did not give OpenAI the green light to release GPT-5.6, nor was that required before a public release under the executive order. They emphasized that all engagement is voluntary. This is a big change in the government's stance on AI. The Trump administration had long been adamant that regulation would slow innovation and cause the US to "lose" the global AI race to China. Now, with government oversight on AI ramping up, it changes the pace of model release and the US's technological reputation on the world stage.