This is an interesting one.
A few days ago, The Cubs Fan relayed a story at LuchaBlog.com from the newest issue of Super Luchas magazine: CMLL, the promotion that Sin Cara worked for as Mistico, has filed for a trademark on the name and image of Sin Cara. Given how strange that sounded, he explained the ramifications of it in a post today.
No, CMLL isn't going to try to create their own Sin Cara. WWE will have no problem booking him in Mexico, selling his merchandise there, airing his matches on Mexican television, etc. If CMLL wanted to sue to try to protect the trademark, they could, but they'd lose because WWE clearly came up with it first.
This is a move about the man behind the mask, the former Mistico. The idea is that if he eventually leaves WWE and comes back to work full time in Mexico, not only could he not be Mistico in other companies like AAA, but he couldn't be Sin Cara, either. As an individual, it would be a lot more expensive and difficult for him to sue CMLL for the right to be Sin Cara than it would to just take on another new name and gimmick.
This seems like a sign that Sin Cara has officially joined Konnan, El Hijo del Santo, and others I'm probably forgetting. Durango Kid is probably on the list for setting up the WWE tryouts that were attended by Mistico/Sin Cara, Averno, and Diamante. Diamante got off with just a suspension after telling the office about Durango Kid's role. Averno may wind up on the list after finishing up.
Speaking of Averno, his mask match with La Mascara is in two days at CMLL's annual Jucio Final event at Arena Mexico. CMLL has announced that the match will not be televised on Galavision or anywhere else for six months, so it will probably show up on a year in review show if it shows up at all. With live attendance for Arena Mexico shows dwindling and AAA also running a major show this weekend, this is a good move to try to draw a good house.