# Patent Evergreening **Patent evergreening** is the practice of extending a drug's monopoly beyond its original patent by filing **thickets** of secondary patents (on dosing, formulation, delivery devices) and by **product hopping** — pushing patients onto a minimally tweaked version before generics arrive. The aim is to delay competition and preserve pricing power. ## Why It Matters Evergreening is a core reason U.S. drug prices stay high long after a drug "should" face competition: blockbuster biologics and small molecules accumulate dozens of patents that deter [[Biosimilar]] and generic entry. It pairs with **[[Pay-for-Delay]]** settlements (paying competitors to stay out) as the two main monopoly-extension tactics. Patent reform and FTC scrutiny of patent thickets are recurring (and industry-resisted) demands in the [[Drug Pricing]] debate. See [[Drug Pricing]] and [[Big Pharma]].