Defendant appeals from a preliminary injunction ordered by the United States District Court for the Southern District of New York (Karas, J.), which enjoined defendant, inter alia, from selling plaintiff’s trademarked products with the unique production code removed. The Court of Appeals (Leval, J.) affirms. Because the production codes play an important role in helping the trademark owner to guard against counterfeits and protect the reputation of the mark, the district court properly found that its unauthorized removal by a seller could justify a finding of trademark infringement.