Last Tuesday, for the first time ever, the Federal Circuit reversed the PTAB in an IPR decision by, among other things, ratcheting back the “broadest reasonable construction” standard for claim construction by declaring the PTAB’s construction “unreasonable.”  The Court said that, “[e]ven under the broadest reasonable interpretation, the board’s construction ‘cannot be divorced from the specification and the record evidence,’ and ‘must be consistent with the one that those skilled in the art would reach.'”  Microsoft v. Proxyconn, 2014-1542, -1543 (Fed. Cir. June 16, 2015) (“A construction that is ‘unreasonably broad’ and which does not ‘reasonably reflect the plain language and disclosure will not pass muster'”) (internal citations omitted).

That claim construction reversal and clarification of broadest reasonable construction is what most people are talking about.  But what might be the more interesting bit in the Proxyconn decision is buried in the footnote on page 25.  The Court reversed the Board’s claim construction, but it affirmed the Board’s denial of Proxyconn’s motion to amend its claims.  In doing so, the Board addressed only that the Board was correct in finding that Proxyconn did not meet its burden to show patentability over the prior art of record.  The Court was careful, though, to say that the Court is not addressing “Idle Free’s requirement that the patentee show patentable distinction over all ‘prior art known to the patent owner.'”

has the Federal Circuit fired a warning shot across the PTAB’s bow indicating that holding patent owner’s to the steep requirement of showing patentability over all known prior art

This blog has followed closely the apparent “PTAB Allows Motion to Amend After It Rejects Original Patent Claims Directed to BioDiesel Fuel,” and very recent “PTAB Relaxing its Application of Law Governing IPR Claim Amendments,” shift in claim amendments during IPR.  Is this footnote simply a responsible remark limiting the holding to the facts of the case, or has the Federal Circuit fired a warning shot across the PTAB’s bow indicating that holding patent owner’s to the steep requirement of showing patentability over all known prior art for claim amendments won’t be tolerated?   We should all know soon enough.