In the US, trademarks are registered with the federal government at the United States Patent and Trademark Office (USPTO). However, not all registrations are automatically granted. Sometimes a trademark registration is refused for a particular reason. One of the most common reasons that a trademark registration is rejected by the USPTO is that there is a likelihood of confusion between the trademark that is seeking registration and a trademark that is already in use in commerce in the United States.

Likelihood of Confusion

When someone is using a trademark that is confusingly similar to a trademark that is already in use, the trademark application will likely be rejected under Section 2(d) of the Lanham Act. The factors that are considered for likelihood of confusion include whether the trademark examiner identified another trademark that is confusingly similar during the trademark search, and whether the trademarks are used for related or similar goods or services. The analysis involves comparing the plaintiff’s trademark to the infringing trademark and looking for similarities, such as:

• Similarity of the appearance of the trademark. The USPTO will consider how similar the visual impressions of the two trademarks are. For instance, if the two trademarks are stylized in a similar manner and the only difference between them is a swapped letter, the marks are likely to be considered confusingly similar – e.g., TRINTSY vs. TRINSTY. When the two trademarks in question are design marks, the likelihood of confusion analysis is focused mostly on the visual appearance of the two marks and how similar they are to one another.
• Similarity of the sound of the trademark. If the two trademarks are read out loud, do they sound the same? For example, if the only difference between the two marks is the substitution of a letter that has a similar sound, such as a “C” for a “K”, the two marks likely sound confusingly similar to one another.
• Similarity in meaning of the trademarks. If the two trademarks are different, but have similar connotation or meaning, it puts consumers at risk of confusing the two marks. For example, PLEDGE and PROMISE are different word marks, but their meaning is very similar. If these two marks are used on products that belong in the same commercial space, there is a substantial likelihood that consumers will be confused.
• Similarity in commercial impression. When two trademarks create the same overall commercial impression in the minds of consumers, a trademark application may be rejected for being confusingly similar to another trademark. Including similar design elements in a trademark that already exist in another trademark can be confusing to consumers.
• Whether the two trademarks are used in the same commercial space. When the two trademarks are used in the same commercial space, consumers are more likely to confuse the two trademarks. However, similar marks can be used in different commercial spaces without risk of consumer confusion. For example, Domino is a trademark for a brand of sugar, and Domino’s is a trademark used for a pizza delivery service. While the two trademarks are similar words, they exist in different commercial spaces.