That's why they have two test sets. But OpenAI has legally committed to not training on data passed to the API. I don't believe OpenAI would burn their reputation and risk legal action just to cheat on ARC. And what they've reported is not implausible IMO.
Yeah I'm sure the Microsoft-backed company headed by Mr. Worldcoin Altman whose sole mission statement so far has been to overhype every single product they released wouldn't dare cheat on one of these benchmarks that "prove" AGI (as they've been claiming since GPT-2).
That's why they have two test sets. But OpenAI has legally committed to not training on data passed to the API. I don't believe OpenAI would burn their reputation and risk legal action just to cheat on ARC. And what they've reported is not implausible IMO.