The idea that Ford might want to discourage others from making a car that looks like a GT40, essentially IS a GT40, presents some interesting opportunities for thought...
As I (no lawyer) understand it, there are two entities at least who have a legal right to the GT40 name/trademark. One is Lee Holman and Holman Automotive, who have a historical link to the original racecar program and who have documentation thereof. The other is Safir GT40 Spares, who purchased the tooling etc for the Mark V cars and who have continued to make spare parts etc many of which will fit original GT40s. The last original chassis mfgr, Tennant, evidently stated they didn't want to be in the chassis business anymore and sent the tooling to Lee Holman, according to Legate's book.
Ford has used the GT40 name lots of times since then, but I think mostly on engine parts and not in a way that necessarily maintains any continuity of use apropos of the original car. Were this issue to come to any legal question, I think it is doubtful that their naming of engine parts "GT40" would preserve any of the claim they might have on the name or image of the car. Moreover, Ford et al went to some trouble in the sixties to distance themselves from the car itself as a Ford, in order to protect themselves from litigation in the event of racing-related injuries or fatalities. They might have trouble reversing themselves on that historical maneuver.
The shape and design of the GT40 have been copied and used so many times over the past thirty years that they would have quite a bit of difficulty, I suspect, in NOW deciding that all of a sudden they wanted to keep anyone else from using the name or shape of the original car. Putting the shoe on the other foot, if someone else had designed and built the car recently introduced by Ford, and Ford had not protected their original design and name by their own use of it, that person or company would have a legitimate case in claiming that the new car, while embodying some elements of the old ones, is sufficiently different that it does not constitute a theft of any trademarked design or name. (much to my chagrin, I now sound like a lawyer. I assure all I am not)
Fortunately, all of us in the GT40 hobby group constitute such a small number that we are not an economic threat to anyone except perhaps our own bankbooks and spousal redecorating plans. And, with their current money woes and downsizing, Ford has bigger fish to fry than automotive hobbyists keeping the image and culture of the world's greatest sports-racing car alive.
Jim R