BuchananPTABReport
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While Congress was debating the provisions of the America
Invents Act (AIA), some lawmakers proposed that inter
partes review (IPR) and post-grant review (PGR) should
be a substitute for invalidity challenges at district court,
such that patent challengers would have to choose one
forum or the other for available challenges. This mutually
exclusive framework was expressed by “could have raised”
estoppel language.[1] Under this “could have raised”
estoppel scheme, patent challengers would essentially get
one chance to raise invalidity contentions before either the
Patent Trial and Appeal Board (PTAB) or the district courts.
If the challenger was unsuccessful before the PTAB, it would
be estopped from raising any prior art challenges at district
court that could have been raised before the PTAB.[2]
To address concerns about the scope of such “could have
raised” estoppel, Congress ultimately limited estoppel
to grounds of challenge “that the petitioner raised or
reasonably could have raised during [an] inter partes review”
or post-grant review.[3] During debate in the Senate,
Senator Kyl remarked that adding the modifier “reasonably”
to the estoppel provisions of the AIA “ensures that could-
have-raised estoppel extends only to that prior art which
a skilled searcher conducting a diligent search reasonably
could have been expected to discover.”[4]
Estoppel applies, on a claim-by-claim basis, when the
PTAB issues a final written decision for a challenged claim.
Estoppel prevents the petitioner from raising or maintaining a
ground of challenge at the Patent Office, in the district courts,
or before the International Trade Commission (ITC) that the
petitioner “raised or reasonably could have raised” during an
IPR or PGR.[5]
The estoppel provisions of the AIA do not contain an explicit
definition of what “reasonably could have raised” means.
The PTAB and the district courts have reached different
conclusions on what “reasonably could have raised” means.
Ironically, the divergence between the PTAB and the district
courts’ interpretation of the scope of estoppel became more
pronounced after the Federal Circuit’s decision in Shaw
Industries Group, Inc. v. Automated Creel Systems, Inc.,[6] in
which the court addressed the scope of estoppel for grounds
of challenge that were denied institution by the PTAB.
Pre-Shaw PTAB Interpretation of Estoppel
Provisions
In two early IPR decisions on the scope of estoppel, PTAB
panels held that the “reasonably could have raised” provision
of 35 U.S.C. § 315(e)(1) applies in a follow-on petition when
the petitioner relies on prior art that the same petitioner
asserted in an earlier-filed petition.
In Dell Inc. v. Electronics and Telecommunications Research
Institute, a panel of the PTAB held that the petitioner
was estopped from asserting an obviousness challenge
based on the Mylex and Hathorn references, because the
same petitioner received an adverse final written decision
in response to an earlier petition in which the petitioner
asserted those references.[7] In the earlier petition, the
petitioner alleged that the claims are anticipated by the
Mylex reference, and that the claims are obvious over the
Hathorn reference in view of other references. The PTAB
panel held that “the differences in how the references have
been asserted in these proceedings have no weight on our
determination of whether the grounds raised in the instant
Petition could have been raised in the [earlier] IPR.”[8] The
PTAB panel concluded that the petitioner could have raised
the obviousness challenge in the follow-on IPR petition
because the petitioner relied on the same prior art in the
earlier IPR petition.[9]
In Apotex Inc. v. Wyeth LLC, a PTAB panel similarly held
that the petitioner was estopped from raising in a follow-
on petition an obviousness ground of challenge (Ground 2)
based on several references that the petitioner was aware
of and cited in an earlier petition for which the petitioner
Under the Same Precedent, Different
Estoppel Standards Have Developed
in the PTAB and the District Courts
February 27, 2017
Jonathan Bowser
