Hatch-Waxman traded patent length for a fast generic pathway.

Generic drugs cost less, but the rules made them nearly impossible to launch because a copy had to repeat years of clinical testing.

The 1984 Drug Price Competition and Patent Term Restoration Act let a generic file an abbreviated application showing only that it is bioequivalent, gave the first firm to challenge a brand patent 180 days of exclusivity, and added patent term back to brands for time lost in review.

The trade created a booming generic industry and a structured contest over patents, turning litigious brand-generic disputes into a regulated market.

Shorten generic entry, lengthen brand patents

An ANDA that relies on brand data removes a huge barrier to entry

Paragraph IV lets a generic fight a patent instead of waiting for it to expire

180-day exclusivity rewards the first firm that takes the risk to challenge

Patent-term restoration keeps the brand innovating despite the challenge

When one rule blocks competition and another blocks innovation, trade them — shorten the copycat path and lengthen the pioneer's patent, so both sides gain.

Hatch-Waxman turned generics into a large, predictable share of US prescriptions and made the Paragraph IV battle and 180-day exclusivity a repeated feature of drug markets, though it is also blamed for evergreening tactics and lengthy patent litigation.