OpenAI previews GPT-5.6 Sol cybersecurity model under government-approved release gate

OpenAI previewed GPT-5.6, a new model family led by Sol, its flagship next-generation model billed as its most advanced cybersecurity AI, alongside Terra (a balanced all-purpose tier) and Luna (the faster, cheaper option). During preview the models are available via API and Codex to select trusted partners only, with the government approving access 'customer by customer' — a staggered release that directly echoes the treatment of Anthropic's Mythos. Sol is priced at $5 input / $30 output per million tokens and includes a sub-agent 'Soul Ultra' mode for deeper reasoning.

The framing is deliberate: OpenAI is treating cyber-capable models as controlled infrastructure, designed to be better at finding and fixing vulnerabilities rather than weaponizing them. OpenAI's Chief Scientist called GPT-5.6 a 'meaningful improvement' over GPT-5.5. The company is also reportedly weighing postponing its IPO to 2027, eyeing either a $1 trillion valuation or a lower, quicker listing.

Competitively, this puts OpenAI in lockstep with Anthropic on government-gated cyber AI — and in sharp contrast with China's Z.ai, whose open-weight GLM-5.2 claims comparable vulnerability-discovery capability with no oversight. That asymmetry is exactly what alarms US officials: tightly controlled domestic models versus freely downloadable foreign ones.

Reaction was mixed. On r/OpenAI, a thread titled 'Scientist early tester on GPT-5.6 Sol' drew 522 upvotes, while Ethan Mollick quipped on X, 'So what model is OpenAI saving the GPT-6 label for?' — capturing version-fatigue sentiment. Skeptics question whether 'find and fix, not attack' is a meaningful distinction for a model this capable, and whether customer-by-customer approval is sustainable as demand scales. What to watch: how quickly Terra and Luna reach general availability, and whether pricing holds post-preview.