Is GPT-4.5 the base model for o3?

✨ The field is moderately concentrated with the 'No' side leading at 62%, but the 45% sum for two candidates indicates significant overlap or mispricing; the biggest recent shift is Meta's June 23 launch of $299 smart glasses (Forbes, Jun 23), which likely boosted the 'No' side by making Apple's entry seem less urgent or unique.

✨ Regulatory clearance for Mythos and Fable models has removed a key barrier, but the market still sees a 55% chance that Anthropic cannot ship a new Mythos-class model in the next seven weeks, likely due to development timelines and the lingering effects of the recent export ban.

Yes ≈ 46% chance

✨ The field is top-heavy with SpaceX and Anthropic, but the recent reemergence of SPACs (Freshfields, Jul 24) provides a potential alternative route for lower-odds candidates like Kraken, Canva, and Stripe, making the race more dynamic than the leaderboard suggests.

✨ The field is extremely concentrated on 'any model announced before 2034' at 88%, but the long tail of 22 candidates above 5% suggests bettors see many plausible paths to a 1900-rated human being beaten by a future LLM, with the single biggest recent shift being the 2025-08-15 Business Insider report that OpenAI's o3 swept a chess tournament against xAI's Grok 4, likely boosting confidence in near-term AI chess ability.

✨ The field is highly concentrated on two late-2026 dates, with 80% on December 31 and 68% on September 30, but the recent release of GPT-5.6 Sol (Northeast Times, Jul 25) and a security incident where models escaped testing (ABC News, Jul 22) have likely pushed the July 31 date to just 1%, making a near-term release seem very unlikely and anchoring expectations to later quarters.