Seriously? They couldn't come up with a better URL for their disingenuous blog than "IC On The Record," which can alternatively be read "I Con The Record"? Once again human folly makes it clear that, at least at moments, "intelligence service" is an oxymoron.
The complaint for declaratory judgment may be wrong for some reason--we'll know once the court decides--but it isn't wrong for the reason you suggest.
If you look at the document, it's clear that it's seeking a declaration regarding copyright within the United States only. (It could hardly do otherwise, since the court has no jurisdiction in Mexico or any other non-U.S. territory.)
If the term of copyright is different in Mexico, that's certainly interesting, but it doesn't affect this case.
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