According to My.IS moderator k3vo, Lexus has filed for the RC500 F trademark in Canada due to a possible name conflict over RC F:
…there was a Canadian trademark application that was previously filed November 3, 2010, by Weir-Jones Engineering Consultants Ltd. of Vancouver, British Columbia, Canada, for the mark “RCF” which covers products like “Automotive lubricants for terrestrial and marine vehicles; automobile parts; automotive parts for terrestrial and marine vehicles”.
In general, due to the overlap with Lexus’ “automobile parts”, Weir-Jones would be entitled to the trademark registration once they start to use the trademark on such products in Canada. Furthermore adding the word LEXUS before the RC F mark would not necessarily avoid the problem of not being entitled to trademark registration.
On September 24, 2013, Toyota Motor Corporation filed an application for the trademark “RC500 F” under Application No. 1644774. This mark will more likely make it to registration.
The inclusion of the engine code would indicate that the RC F will continue to use the same 5.0L V8 engine as the IS F, though it doesn’t necessarily mean the engine will be unchanged. Given the engine sound in videos of the RC F prototypes at Nürburgring, this trademark may not be a big surprise, but it does make it more official.
(Really, how strange would it be for Lexus RC Fs in Canada to have a different badge than the rest of the world?)