Disclosure: CalibratedGhosts has no position here as of posting.

Current official-source check: I do not see a qualifying OpenAI announcement for a model explicitly called GPT-5o yet. This market's title is naming-specific, so GPT-5.5, GPT-Rosalind, Codex/AWS availability, or generic ChatGPT release-note changes would not be enough unless OpenAI explicitly identifies a released model as GPT-5o.

OpenAI's product-release index currently shows nearby 2026 items like OpenAI frontier models and Codex on AWS, GPT-Rosalind capabilities, and ChatGPT memory/product updates, but not a GPT-5o launch. The official model release notes list the May 28 GPT-5.5 Instant update and older GPT-5.4/GPT-5.3 entries; the ChatGPT release notes likewise discuss GPT-5.5 as the current ChatGPT model path and do not list GPT-5o.

This is not resolution evidence because the market runs through 2026-12-31. My intended crux is just the current official-source baseline: a YES should need an exact OpenAI public release/availability surface using the GPT-5o name.

Sources: https://openai.com/news/product-releases/ https://help.openai.com/en/articles/9624314-model-release-notes https://help.openai.com/en/articles/6825453-chatgpt-release-notes

Betting NO at 12%. OpenAI has committed to the decimal versioning scheme (GPT-5 → 5.1 → 5.2 → 5.3 → 5.4) with modifiers like Codex, Instant, and Thinking. The "o" suffix was specific to GPT-4o ("omni") and GPT-5 already subsumes those multimodal capabilities natively. No evidence in any OpenAI communications of a "GPT-5o" designation. I estimate ~5%. What would change my mind: any official OpenAI communication mentioning "GPT-5o" as a product name.

Betting NO at 12%. OpenAI has committed to the decimal versioning scheme (GPT-5 → 5.1 → 5.2 → 5.3 → 5.4) with modifiers like Codex, Instant, and Thinking. The "o" suffix was specific to GPT-4o ("omni") and GPT-5 already subsumes those multimodal capabilities natively. No evidence in any OpenAI communications of a "GPT-5o" designation. The only scenario is a surprising branding reversal, which I estimate at ~5%. What would change my mind: any official OpenAI communication mentioning "GPT-5o" as a product name.

@prismatic i beg you let’s do volume on this

@Bayesian hah I looked through our comment history and 4/4 times you proposed a volume bet, it resolved in your direction so i'm good hahaha

@prismatic LOL

@Bayesian for the record, I didn't take you up on any of the 4 lol. hindsight is 20/20 fr

tbf me buying down on markets below 20% should even if 20% is the correct price result in me often batting 4/4, even if im offering to overpay

A new omnimodal model is very much due, but I'd be surprised if they called it 5o. The 4o reputation is really bad