In Straight Path IP Group, Inc. v. Sipnet EU S.R.O., Appeal No. 2015-1212, the Federal Circuit reversed the PTAB’s construction of a claim term in an IPR, reiterating that, absent clear redefinition or disavowal, the plain meaning of a claim limitation will be controlling over other descriptions in the specification when the plain meaning is unambiguous.

In Sipnet’s IPR against Straight Path’s patent, the PTAB canceled claims based on its construction of the claim term “a query as to whether the second process is connected to computer network.”  The parties agreed that the claim term’s language requires "being on-line," however, the PTAB adopted Sipnet’s view that the language also “simply requires being registered with the server,” and not Straight Path’s view that it “refers to a present-tense status.” In reaching its conclusion, the PTAB asserted that Sipnet’s construction was the “broadest reasonable construction based on the specification” because “‘connected to the computer network’ encompasses a processing unit that is ‘active and on-line at registration.’”

Straight Path appealed, arguing that (1) because the patent had expired by the time of the appeal (but apparently not at the outset of the IPR), the Federal Circuit should address claim construction under the principles of Phillips rather than using the broadest reasonable interpretation standard, and (2) the PTAB reached the wrong claim construction even under the broadest reasonable interpretation standard.  The Federal Circuit chose not to address issue (1) because it found in issue (2) that the PTAB’s construction was erroneous even under the broadest reasonable interpretation standard. 

In a de novo review of the PTAB’s claim construction, the Federal Circuit focused on the word “is” within the claim term and held that the language “plainly says” that the query must address the present-tense status of the second process.  The Federal Circuit held that “the PTAB did not address the facially clear meaning [of the claim language], instead turning immediately to the specification.”  The Federal Circuit explained that, “[w]hen claim language has as plain a meaning on an issue as the language does here, leaving no genuine uncertainties on interpretive questions relevant to the case, it is particularly difficult to conclude that the specification reasonably supports a different meaning.  The specification plays a more limited role than in the common situation where claim terms are uncertain in meaning in relevant respects.”  Because there was no basis for reasonably adopting a construction that contradicts the plain meaning of the claim language, the PTAB erred in its construction even under the broadest reasonable interpretation standard.  The Federal Circuit reversed the construction and claim cancellation, and remanded for further proceedings.