As most of our readers likely know, IPR estoppel means that an accused infringer who brought an IPR cannot claim invalidity at trial on a grounds it reasonably could have raised during the IPR. But what constitutes a "grounds" for invalidity has varied across different District Court judges.
Everyone agrees that, as the statute says, the PTAB cannot address system or product prior art under the on-sale bar, but can potentially address publications describing those products. There has long been a split of precedent on whether an accused infringer covered by IPR estoppel can argue invalidity based on a prior art product, where the documentation describing the production could have been asserted in the IPR …
