Red is an American company (Irvine, CA). If reverse engineered and unlicensed, they have violated patent laws. They licensed the mount. The movie houses like Canon glass.
BTW: Red is suing Sony (still ongoing) over violating some of it's 4K tech patents (3 of them). The suit (filed in 2013) demands Sony not only stop using the tech Red invented, but also destroy all cameras manufactured with it. Uh oh.
"What's interesting about this case is that patent issues or licensing could be one of the reasons most companies have not tackled RAW compression in their motion picture cameras. Canon and Arri are both sending out uncompressed RAW to third-party recorders (and avoiding recording internally altogether), and Blackmagic, Digital Bolex, Ikonoskop, and Aaton are all recording uncompressed CinemaDNG internally to SSDs. CinemaDNG is an open format from Adobe, but recently they developed a compressed JPEG option for their stills DNG archive format. We'll see if that finds its way into motion cameras and if that development potentially infringes on any RED patents." (year 2013 for perspective)
https://nofilmschool.com/2013/02/red-ceo-jim-jannard-lawsuit-sony-raw-compression
Red has been in 4K since 2005.
Speculation: Maybe Red and Canon are exchanging licenses? Give us your RF mount and we'll give you some 4K tech. Revenge by Red? What better way to destroy Red's (and Canon's) nemesis? Especially if those patents by RED are running out soon. RED doesn't make lenses. RED makes mounts available for Canon, Nikon, Leica, and ARRI PL. No Sony mount is offered by RED.
Yes, I am aware that the suit has to do with movie cameras but still....
So for those who say Canon could do what Sony has done in it's mirrorless cameras, maybe so. But maybe Canon has had trouble bringing something to market due to patent issues. More kudos to Canon for not stealing tech as RED alleges Sony to have done. Untwist yer pantaloons.