A likelihood of confusion between two trademarks exists when a consumer is likely to cause consumer confusion between different sources. A likelihood of confusion is a main factor for determining trademark infringement, as well as trademark registrations through the USPTO.
For infringement, each circuit court has a factor-based test to determine a likelihood of confusion. For example, the 11th Circuit, which includes Florida, includes the following factors in a likelihood of confusion analysis: 1) the strength of the mark; 2) the similarity of the marks; 3) the similarity of products or services; 4) the similarity of customers and trade channels; 5) the advertising similarities; 6) the infringing party’s intent in using the mark; and 7) evidence of actual confusion. See Lone Star Steakhouse & Saloon, Inc. v. Longhorn Steaks, Inc., 122 F.3d 1379, 1382 (11th Cir. 1997).
In addition, for trademark examination, the Trademark Office considers the du Pont factors from In re E.I. du Pont de Nemours & Co., 476 F.2d 1357 (CCPA 1973). These factors include 1) the similarity between the marks regarding appearance, sound, connotation, and commercial impression; 2) the relatedness of the goods; 3) the similarity of trade channels; and 4) the consumer purchasing conditions.