Genericide is what happens when a trademark becomes a victim of its own success: consumers stop treating the term as identifying a particular source and start using it as the everyday name for the whole category of product. Once a mark becomes generic, it can no longer function as a trademark and protection is lost, sometimes leading to cancellation of the registration.

Courts apply the primary significance test, asking whether the primary significance of the term to the relevant public is the product category itself or a particular source. Owners defend against genericide by actively policing improper generic usage in media and by competitors, maintaining brand style guides, and commissioning genericness surveys to demonstrate the mark still functions as a source identifier.

In a simulation, brand-strength erosion is naturally modeled as a decaying dial over time, since genericide risk typically accumulates gradually through years of usage patterns rather than through a single triggering event, and the model can flag when that dial crosses the threshold that flips a mark's protectability status.

Brand owners invest in active policing of their marks, correcting improper generic usage in press and marketing materials and pursuing enforcement against competitors who use the mark generically, and they commission genericness surveys to defend against attacks on distinctiveness. Litigators raise genericide as an invalidity defense to try to cancel or defeat enforcement of a mark that has, in their view, become the common name for the product.