Yes - and remember - the law in question, the Magnuson-Moss Act - simply governs that a warranty can't be contingent on only using OEM equipment. E.g. - Apple can't say, "Your warranty is void unless you use Genuine apple drives, purchased from an authorized Apple outlet."

There is - however - no provision on making it an absolute pain in the ass to manufacture or implement 3rd party aftermarket equipment.

More info from the FTC here: http://business.ftc.gov/documents/bus01-businesspersons-guid...

The relevant section is under "Tie-In Sales".