The New Prior User Rights Defense: How Often Will It Be Asserted?

Before the America Invents Act (AIA), the prior-user defense to infringement was limited to "method[s] of doing or conducting business." While rarely relied on during litigation, the defense allowed the continued use of a business method in secret despite a later issued patent. Under the AIA, congress sought to expand the scope of the prior user rights under 35 U.S.C. § 273 to be commensurate with protections in many other countries.

The prior user defense now applies to any process, as well as any "machine, manufacture, or composition of matter used in a manufacturing or other commercial process," so long as this subject matter is "commercially used" at least one year before the effective filing date of the claimed invention. But will this broadened language substantially expand the use of § 273? Possibly no.