United Drug Co. v. Theodore Rectanus Co.

Regis began using the "Rex" mark in Massachusetts in 1877, later selling those rights to United Drug (plaintiff), which expanded into Louisville, Kentucky in 1912 and sued Rectanus (defendant), who had independently and in good faith used the identical "Rex" mark in Louisville since 1883 with no knowledge of Regis's use; the district court granted United Drug an injunction based on its earlier first-use date, but the court of appeals reversed, finding Regis never tried to establish the mark outside New England.