Tamron USA has begun teasing four new mirrorless lenses on their Facebook page.
There's no mention of what the four lenses are as of yet, or what mount(s) these lenses will be available for. I think it's still a bit early to see third party autofocus lenses for Canon's RF mount from Tamron or SIGMA, but surprises do happen.
Tamron currently has 2 mirrorless lenses for Sony's FE mount, so it's likely these will be for Sony as well. Judging by the teaser, it looks like a telephoto zoom lens and three prime lenses are coming.
I do not remember seeing patents about RF protocol. I have not searched for them, though, but since there seem to be a few people covering Canon patents (at least you, Canon News and Northlight), they should have been found already. Have you or others seen such? The downside of patents is that patents are public. Maybe Canon has encrypted the protocol or at least made it hard to reverse engineer?
Also, as there are new features still to come to the R system (e.g. Dual IS) that may require additional features in the protocol, it may be risky to bring RF products to the marketplace just yet.
Right. Has it been confirmed that there is no active protocol translation happening in the adapter, though? I have read strong opinions with some kind of evidence that EF signals are just passed through, but I am not convinced. And even if the signals were just passed through, there may be a handshake sequence between the EF-RF adapter and the body when an adapted EF lens is attached, which would have to be hacked anyway to be able to emulate it.
Emulating an EF lens should be still fine, though.