As Mickey Mouse turns 80 this fall, the most beloved rodent in show business is widely regarded as a national treasure -- and owned lock, stock and trademark ears by the corporate heirs of his genius creator.

Brand experts reckon his value to today's Walt Disney Co. empire at more than $3 billion. Acts of Congress have extended Mickey's copyright so long that they provoked a Supreme Court challenge, making Mickey the ultimate symbol of intellectual property. All signs pointed to a Hollywood ending with Disney and Mickey Mouse living happily ever after -- at least until a grumpy former employee looked closely at fine print long forgotten in company archives.

Film credits from the 1920s reveal imprecision in copyright claims that some experts say could invalidate Disney's long-held copyright.

& #8226; Read the full Los Angeles Times story.

For reprint and licensing requests for this article, CLICK HERE.