Today, the Federal Circuit will hear oral argument in the BTG v. Amneal Pharmaceuticals case.  In addition to standard disputes over whether the patent-in-suit was obvious and whether it was infringed, this case presents a novel issue regarding estoppel for IPR petitioners.

Essentially, the question is whether a petitioner who successfully challenges a claim at the PTAB is barred from arguing invalidity of that claim in district court.  BTG—and the USPTO, in an amicus brief—argues that if you win at the USPTO, you thereby have to lose at district court, at least until all rehearings and appeals are exhausted.

Appeals are a process that can take years—years during which you might be barred from putting your product on the market, even though the USPTO already said that there was no valid patent blocking your path.  

Amneal (and an amicus brief from the Association for Affordable Medicine) point out that this result is counter-intuitive—which the USPTO admits in its own brief—and that normal principles of estoppel prevent making arguments contrary to previous arguments or results, rather than preventing a prevailing party from adopting the prevailing position it had already taken.

It’s unclear how the USPTO brief in this case, insisting that a petitioner who wins at the PTAB cannot argue that the patent was invalidated at the PTAB, meshes with the USPTO’s stated position that getting the same results at the district court and the PTAB is an important goal.  If the USPTO Director truly believes that the statute requires this counter-intuitive result, perhaps he could push for a legislative fix that would make sure that a win at the PTAB doesn’t hurt petitioners.