[trebleshot]

I know that Hasbro has said that movie toys are off-limits to Botcon or other conventions wanting to do exclusives. The reason I stated that the toys would be co-owned is that regardless of how he looks, Optimus Prime is a trademarked character owned by Hasbro. Dreamworks/Paramount may co-own likeness rights to that particular version of Prime, but ultimately Hasbro still owns Prime. Keep in mind, the "Revenge of the Fallen" logo is co-owned by Hasbro and the studios, so that alone would warrant the Dreamworks and Paramount logos to appear on the package.

Now, I'm no expert in copyright laws, but I would think "style" is too vague for the Patent office. I know to obtain a copyright, you have to be very specific about it. Anything too vague or generic won't pass anymore. Otherwise, what's to stop Hasbro from suing over the C.O.R.P.s figures, since they're the same "style" as G.I.Joe (i.e. 3.75"-scale military-themed posable/articulated action figures). Or Disney suing Dreamworks over their animation style.

Chances are, the real reason most of the movie toys are off-limits is because either Hasbro would have to pay the studios residuals and/or that the studios would be involved in the approval process.

There's also a third possibility: most retailers love the movie line, so Hasbro doesn't want anyone but themselves to release redecos of those toys since Hasbro might do it themselves at some point. Nine times out of ten, the reason TFCC is unable to use a mold for a particular character is because Hasbro's planning to do it themselves at some point.