If you read the article (which I know no one does anymore)

>OpenAI and its partner Microsoft investigated accounts believed to be DeepSeek’s last year that were using OpenAI’s application programming interface (API) and blocked their access on suspicion of distillation that violated the terms of service, another person with direct knowledge said. These investigations were first reported by Bloomberg.

They might show DeepSeek's model calling itself ChatGPT, which users have already alleged. Same as how Cisco proved Huawei was stealing router code.

Except in this case, nothing was stolen, unless they want to call ChatGPT's own training on source data theft too.

ChatGPT outputs are all over the internet. It is harder to prove that deepseek used specifically o1 for training, instead of a lot of chatgpt output ending up in the training set from other sources.

That's a good point, at least for the prompts I saw. Like "do you have an app I can use" is commonly seen with "here's the ChatGPT app" online. And maybe they don't add anything telling Deepseek that it's Deepseek.