TL;DR: OpenAI released GPT-5.4 Thinking and GPT-5.4 Pro on March 5, 2026. GPT-5.4 Pro is likely the best model in the world for many catastrophic risk-relevant tasks, including biological research R&D, orchestrating cyberoffense operations, and computer use. GPT-5.4 Pro has no system card, only GPT-5.4 Thinking, and, to our best knowledge, Pro has been released without any safety evals. We argue this has occurred at least once before, with GPT-5.2 Pro, and provide recommendations for how a team could conduct fast, independent risk assessments of models post-deployment.
IMPORTANT EDIT: This problem, where Pro models don't have a safety card, has existed since at least o3-pro. Others have noticed this issue before (for o3 and GPT-5). Additionally,... (read 1227 more words →)