Utilitarian functionality provides grounds to deny federal trademark protection to product features which do something useful.
Aesthetic features are within the purview of copyright law, which provides protection to creative and original works of authorship.
The Federal Circuit in contrast focuses its analysis on whether permitting a product feature to be trademarked would impair competitors.
Thus, the functionality doctrine serves to prevent trademark owners from inhibiting legitimate competition [11] When the aesthetic development of the good is intended to enhance the design and make the product more commercially desirable, trademark protection may be denied because the consumer is drawn to the design.
The distinctiveness of the mark serves to identify the product rather than the source, and trademark protection becomes inappropriate.