I believe it, when I see it.

Have they published?

Previous discussion here (with links to actual primary source):

https://news.ycombinator.com/item?id=48023079

No technical report published yet, unlikely code or weights will be either given VC funding.

It’s probably something like deepseek’s native sparse attention with content based granularity. They might not be publishing anything because it’s not such a strong value proposition and doing so would lead to commentary that would tank their investment opportunities.