What is the purpose of trademark law?  To prevent unfair competition by (a) providing assurance that goods/services are of a certain quality/consistency, and, critically,  (b) assisting consumers in making purchasing decisions. For example, if I go to a McDonald’s restaurant in McLean or Richmond,  I am (generally) guaranteed the same type of restaurant service.  Again, the objective is to grant certainty to the consumer and, by doing so, to build goodwill in favor of the producer.

The problem arises when the producers (or trademark holders) have a dispute concerning whether Company A or Company B is entitled to use a particular mark or brand to identify its goods and services.  It is in that situation that reasonable minds can differ as to whether the marks are confusingly similar.  Eventually, if the businesses cannot work it out between themselves, the lawyers get invited to the party. 

For example, you started a pest control company a decade ago and use in your advertising the slogan “We will eat them up.”  A neighboring Mexican restaurant starts up a few years later and uses the tagline “You will eat us up.”  Problem?  I don’t think so (although there is hopefully no cross-distribution agreement between the pest company’s kills and the restaurant’s food products).  And why is that?  Because the companies are not in the same industry and there would be no customer confusion.

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