Why DeepSeek's new AI model thinks it's ChatGPT

Earlier this week, DeepSeek, a well-funded Chinese AI lab, released an "open" AI model that beats many rivals on popular benchmarks. The model, DeepSeek V3, is large but efficient, handling text-based tasks like coding and writing essays with ease.

It also seems to think it's ChatGPT.

Posts on X — and TechCrunch's own tests — show that DeepSeek V3 identifies itself as ChatGPT, OpenAI's AI-powered chatbot platform. Asked to elaborate, DeepSeek V3 insists it is a version of OpenAI's GPT-4 model released in 2023.

The delusions run deep. If you ask DeepSeek V3 a question about DeepSeek's API, it'll give you instructions on how to use OpenAI's API. DeepSeek V3 even tells some of the same jokes as GPT-4 — down to the punchlines.

So what's going on?

Models like ChatGPT and DeepSeek V3 are statistical systems. Trained on billions of examples, they learn patterns in those examples to make predictions — like how "to whom" in an email typically precedes "it may concern."

DeepSeek hasn't revealed much about the source of DeepSeek V3's training data. But there's no shortage of public datasets containing text generated by GPT-4 via ChatGPT. If DeepSeek V3 was trained on these, the model might've memorized some of GPT-4's outputs and is now regurgitating them verbatim.

"Obviously, the model is seeing raw responses from ChatGPT at some point, but it's not clear where that is," Mike Cook, a research fellow at King’s College London specializing in AI, told TechCrunch. "It could be 'accidental' … but unfortunately, we have seen instances of people directly training their models on the outputs of other models to try and piggyback off their knowledge."

Cook noted that the practice of training models on outputs from rival AI systems can be "very bad" for model quality, because it can lead to hallucinations and misleading answers like the above. "Like taking a photocopy of a photocopy, we lose more and more information and connection to reality," Cook said.