## Facts

- Munsingwear manufactured men’s underwear featuring a horizontal-fly design beginning in 1946.
- In 1992, Jockey introduced men’s underwear with a horizontal fly that Munsingwear alleged was confusingly similar to its product design.
- Each party sold the underwear in packaging prominently identifying its own brand name, and the packaging was not similar in overall appearance.
- Munsingwear asserted trademark and trade dress infringement (including under Lanham Act § 43(a), 15 U.S.C. § 1125(a)) and related deceptive trade practices based on alleged consumer association between Jockey’s product and Munsingwear.
- Munsingwear emphasized a post-sale confusion theory, arguing that once the underwear was out of its packaging, the horizontal fly could act as a source identifier.
- Jockey contended that confusion should be assessed principally in the pre-sale context, where consumers encountered clearly labeled packaging.

## Issues

1. Whether Munsingwear produced sufficient evidence of a likelihood of confusion to support trademark/trade dress claims under Lanham Act § 43(a) and related theories.
2. Whether the likelihood-of-confusion analysis should focus primarily on pre-sale conditions (packaging and point-of-purchase) or post-sale conditions (appearance of the product out of packaging).
3. Whether summary judgment for Jockey and denial of a preliminary injunction were proper given the record on likely confusion.

## Decision

- The district court denied Munsingwear’s motion for a preliminary injunction and granted Jockey’s motion for summary judgment.
- The district court found no likelihood of confusion and no genuine dispute of material fact that could permit a reasonable jury to find otherwise; therefore, Munsingwear could not establish a prima facie infringement case.
- The Eighth Circuit affirmed in an unpublished per curiam decision, finding no prejudicial legal error and affirming the judgment.
- The Eighth Circuit noted the district court referenced an outdated version of Lanham Act § 43(a), but held the mistake was harmless because the record still showed no material dispute of fact on confusion as to affiliation, connection, association, origin, sponsorship, or approval.

## Legal Principles

- Likelihood of confusion is a required element for trademark and trade dress claims under Lanham Act § 43(a), including confusion about affiliation, connection, association, origin, sponsorship, or approval.
- Summary judgment is appropriate where the record shows no genuine dispute of material fact and no reasonable factfinder could find a likelihood of confusion.
- Prominent, non-similar packaging and clear source identification at the point of sale may defeat a claim that consumers are likely to be confused about source.
- Post-sale confusion theories require concrete evidentiary support; similarity in a product feature visible after purchase, without more, may not create a triable issue when pre-sale source identifiers are clear.
- An incorrect statutory citation does not require reversal if the error does not affect the outcome and the substantive analysis remains consistent with the governing law.

## Conclusion

The courts rejected Munsingwear’s trade dress and trademark theories because the record did not support a likely confusion finding, particularly given clear pre-sale branding and the absence of a material factual dispute; the Eighth Circuit affirmed and treated the district court’s outdated statutory reference as harmless.


Munsingwear, Inc. v. Jockey Int’l, Inc., 31 U.S.P.Q.2d 1146 (D. Minn. 1994), aff’d, 39 F.3d 1184 (8th Cir. 1994)