Funny how a fact can become so much more. There is no "official" 3rd party lens ban from Canon. Of course, this is the internet, so why bother with accuracy? Canon had two (I think it was two) 3rd party lens makers stop their production of AUTO FOCUS lenses
due to patent infringement. At no time, to my knowledge, did they announce any sort of ban or official policy of any kind. People on the internet interpreted their actions to be a ban, some people going so far to say that there would NEVER be any 3rd party lenses allowed. The possibility of reverse engineered lenses seems to be avoided. Only a few weeks ago at CP+, Canon developers spoke about 3rd party lenses:
Canon developers interviewed at the recent CP+ 2023 venue in Japan said this.
Via Google translate :
"Certainly, there have been many inquiries from third parties, and we have listened to their requests.
However, we do not have direction or policy on this matter. I cannot give details, but if it is in line with our strategy, we will take necessary measures on a case-by-case basis. One example is the launch of Cosina's RF lenses. Cosina's Voigtlander 50mm F1 is the first 3rd party lens that can communicate with the body via an RF mount.
We are in talks with other manufacturers."
Does this mean we should expect 3rd party AF lenses any time soon? No, I doubt it. But let's not rush to conclusions either, that it will never happen. We just don't know, which I understand frustrates people, so they make up their own answers instead of being patient and waiting for the real answer.