Harley-Davidson is cruising toward a new frontier: It's trying to trademark a noise.
The Milwaukee motorcycle maker, already the owner of the copyright for the word "Hog," has filed a petition with the U.S. Patent and Trademark Office for exclusive rights to its engine sound.
If the company succeeds, the aural emission of its "45 degree V-twin single crankpin motor" would join the roar of the MGM lion and the NBC chimes as trademarked sounds.
But experts say Harley may have a hard time proving its engine noise is both unique and closely associated with its brand, the standards for trademarking a sound.
"There's nothing intrinsically impossible in saying when you have this sound, it's a Harley-Davidson," says Arthur Miller, an intellectual-property expert at Harvard Law School. "But they have to prove that."
Harley-Davidson claims that the trademark is needed because rival manufacturers are already trying to mimic the noise.
"We feel there's a competitive threat," says Steve Piehl, a Harley spokesman. "A lot of our owners tell us they buy a Harley just for the sound."