If the clean room re-write was done entirely by Claude, then the result cannot be copyright in the USA, and thus there is no license at all.
And if he was in fact more involved (which he appears to deny) that it's a bit weak to say that someone with huge familiarity with chardet could choose to reimplement chardet without the result being derivative.
There's a difference between "I've read a LGPL code once, maybe I could do something similar" and "I've been reading this LGPL code for 12 years and now I'm going to do exactly the same thing".
