They should have used a zero data retention agreement, user error

I suspect this controversy will blow the case for ZDR wide open. Whatever the facts (possibly unknowable), it's going to become a very public lesson that data sovereignty was never about "having nothing to hide".

If this is what they do to academic pure mathematicians, where the stakes are so low (financially)—just imagine the sort of front-running that could be happening in other places.

Yeah if I was Anthropic this would be part of my marketing strategy.

How so? OpenAI and anthropic have basically the same retention policies

Hahaha, how exactly is an individual user supposed to get a ZDR agreement?

I doubt it would've made any difference, zero data retention is truly trivial to get around and I think it's highly likely OAI is already doing this. Just use another model to distill, summarize, and/or paraphrase the data and boom - you get to train on the ideas, while claiming zero data retention, which is true. You legitimately retained zero data.