Timeline
Study reveals GPT-5 exhibits central tendency bias in clinical scoring, compressing predictions toward scale midpoint.
GPT-5.5 fully solved TLO enterprise network simulation in 2 of 10 attempts
GPT-5.5 scored 71.4% on AISI expert CTF tasks, matching Claude Mythos Preview
Early user review of GPT-5.5 in Codex highlights major improvements
GPT-5.5 model family achieves leading position on Artificial Analysis Index for cost-performance
OpenAI engineer reveals GPT-5.5 is a Blackwell-native model trained on Nvidia GB200/GB300 NVL72 systems.
GPT-5.5 spotted via Codex API backdoor, suggesting unofficial release channel for image generation.
Evaluation study published on arXiv assessing its clinical reasoning capabilities
Reportedly became available according to user social media post