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Lapp test

The Lapp test is the standard used to determine whether a likelihood of confusion exists between two trademarks. Under the Lanham Act, liability for trademark infringement is based on a finding that the use of one trademark causes a likelihood of confusion with another previously established trademark. A likelihood of confusion exists when an allegedly infringing trademark is likely to cause an appreciable number of reasonably prudent purchasers to be confused as to the source or origin of the products or services it is used to identify.

The Lapp test is a multi-factored test used to establish the existence of a likelihood of confusion. The Lapp factors include: 

  1. The degree of similarity between the owner's mark and the alleged infringing mark; 
  2. The strength of the owner's mark; 
  3. The price of the goods and other factors indicative of the care and attention expected of consumers when making a purchase; 
  4. The length of time the defendant has used the mark without evidence of actual confusion arising; 
  5. The intent of the defendant in adopting the mark; 
  6. The evidence of actual confusion; 
  7. Whether the goods, though not competing, are marketed through the same channels of trade and advertised through the same media; 
  8. The extent to which the targets of the parties' sales efforts are the same; 
  9. The relationship of the goods in the minds of consumers because of the similarity of function;
  10. Other facts suggesting that the consuming public might expect the prior owner to manufacture a product in the defendant's market, or that he is likely to expand into that market.

See: Interpace Corp. v. Lapp, Inc., 721 F.2d 460 (3d Cir. 1983).

The Lapp test is a non-exhaustive list of factors relevant to assessing the likelihood of confusion. Not all factors will be relevant in all cases, and the different factors may be given different weights depending on the circumstances of each particular case. No single factor is dispositive and a finding of a likelihood of confusion does not require a positive finding on a majority of the factors listed. The Lapp factors are intended as a guide; a court is free to consider any other relevant factors in determining whether a likelihood of confusion exists.

[Last updated in June of 2023 by the Wex Definitions Team]