Trademark dilution

Trademark dilution is a trademark law concept giving the owner of a famous trademark standing to forbid others from using that mark in a way that would lessen its uniqueness. In most cases, trademark dilution involves an unauthorized use of another's trademark on products that do not compete with, and have little connection with, those of the trademark owner. For example, a famous trademark used by one company to refer to hair care products might be diluted if another company began using a similar mark to refer to breakfast cereals or spark plugs. Dilution is a basis of trademark infringement that only applies to famous marks. With non-famous marks, the owner of the mark must show that the allegedly infringing use creates a likelihood of confusion as to the source of the product or service being identified by the allegedly infringing use. With non-famous marks, it is highly unlikely a likelihood of confusion will be found if the products or services are in unrelated markets. However, with famous marks, any use by another person of the mark has the potential for confusion, since a famous mark is so well known among the consuming public that people will assume affiliation with the owner of the mark regardless of the product or service being sold under the infringing use.

Trademark law traditionally concerned itself with situations where an unauthorized party sold goods that are directly competitive with or at least related to those sold by the trademark owner. A trademark is diluted when the use of similar or identical trademarks in other non-competing markets means that the trademark in and of itself will lose its capacity to signify a single source. In other words, unlike ordinary trademark law, dilution protection extends to trademark uses that do not confuse consumers regarding who has made a product. Instead, dilution protection law aims to protect sufficiently strong trademarks from losing their singular association in the public mind with a particular product, perhaps imagined if the trademark were to be encountered independently of any product (e.g., just the word Pepsi spoken, or on a billboard).

The strength required for a trademark to deserve dilution protection differs among jurisdictions, though it generally includes the requirement that it must be distinctive, famous, or even unique. Such trademarks would include instantly recognizable brand names, such as Coca-Cola, Kleenex, Kool-Aid, or Sony, and unique terms that were invented (such as Exxon) rather than surnames (such as Ford or Zamboni) or ordinary words in language. Some jurisdictions require additional registration of these trademarks as defensive marks in order to qualify for dilution protection.

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