OpenAI's GPT-5.6 family — Sol, Terra, and Luna — became broadly available Thursday after spending 12 days gated behind a U.S. government review that was, legally speaking, entirely voluntary, and that functioned, practically speaking, like preclearance. The clearance followed additional testing by the Commerce Department's Center for AI Standards and Innovation (CAISI) and direct technical engagement between OpenAI engineers and government officials in Washington. On June 26, OpenAI previewed the GPT-5.6 family and simultaneously agreed to restrict access at the request of two White House offices under the framework President Trump established in his June 2 executive order, "Promoting Advanced Artificial Intelligence Innovation and Security." GPT-5.6 is a tiered model family differentiated primarily by capability and cost: Sol is the flagship for hardest agentic tasks; Terra is the everyday production tier; Luna is the high-volume, speed-optimized option. Pricing is Sol at $5 per million input tokens and $30 per million output tokens; Terra at $2.50 and $15; Luna at $1 and $6. OpenAI is also launching Sol on Cerebras infrastructure capable of serving it at up to 750 tokens per second. Access expands across ChatGPT, the API, and Codex simultaneously.