A trademark can lose its distinctiveness if it comes to be used as a synonym for the product itself, and no longer serves as an indicator of the origin (maker) of the product. When this happens, trademark protection is said to be lost through “genericide.”
Genericide can be a major disaster for a company that has invested many thousands of dollars registering and enforcing a trademark.
Some famous trademarks that have fallen victim to genericide include:
Aspirin (in the U.S.)
Cellophane (in the U.S.)
Walkman (in Austria)
Some trademarks that are at risk (or have recently been at risk) of genericide include:
Bubbler (thanks to Wisconsinites)
Coke (thanks to Southerners)
Google (recently survived challenge)
Gu (runners understand)
Swiss Army Knife
(These are not exhaustive lists.)
There are a number of steps you can take to help prevent genericide. For example, it is a good idea to always use your trademark as an adjective, never as a noun or a verb. (Say “Kleenex brand tissues are the best,” not “Kleenexes are best.” ) Some companies include anti-genericide provisions in their license agreements. For more ideas about what you can do to protect your brands, consult a trademark attorney.