Merck's dispute with Aurobindo put patent term extensions for reissued patents at the center of a Federal Circuit Hatch-Waxman decision.
Patent term extension compensates drug innovators for time lost during regulatory review. The appeal required the court to apply that framework when the asserted patent had been reissued.
The case is commercially important because even small term-extension questions can decide generic-entry timing. For branded companies, reissue strategy must be modeled against regulatory timelines rather than treated as a prosecution-only issue.
For generic challengers, the decision belongs in the launch-risk file: expiration dates, reissue certificates, and PTE calculations are often as consequential as infringement theories.