A unanimous Supreme Court held that whether a later mark may 'tack' onto an earlier mark's priority date is a question for the jury—locating the decisive moment in a clearance dispute in the fact-finder's assessment of consumer perception.
The Federal Circuit's analogous-use decision held that promotional activity can establish trademark priority before sales — but only on proof that it reached a substantial portion of the relevant consuming public, not merely that the user intended an association.
The Seventh Circuit's ZAZU decision held that token sales and an intent to register cannot establish trademark priority — only genuine market use that links the mark to a source in consumers' minds will do.
The Second Circuit's foundational concurrent-use decision held that a federal registrant cannot enjoin a good-faith remote junior user until it is likely to expand into that user's trading area — a rule that still shapes every trademark clearance opinion.
