Next, the discussion turns to practical applications. Use of the consumer investment model would keep trademark doctrine on a principled path that preserves the public interest in using marks as information tools. The model offers a new way of examining difficult issues involving the unauthorized use of brands on the Internet. Specifically, in keyword advertising disputes, the model would prompt courts or Congress to weigh public informational interests when considering how much control mark owners should exert over their brands on the Internet. However, as technology advances and new uses for marks evolve, the model would not block trademark expansion. It simply would provide a constant reminder to consider public interests. For example, the model generally supports dilution protection for famous marks. However, this Article introduces “cultural dilution” as a type of lost distinctiveness that should be exempted from trademark protection. Cultural dilution occurs when consumers invest a famous mark with new meaning through viral means that brand owners cannot stop. Finally, this Article recommends creation of a safe harbor for reference materials to reflect actual consumer understandings of terms that also serve as brands. Application of the consumer investments model in these contexts and others would assure that actual consumer interests are weighed in trademark disputes that affect public access to information.