A recent decision from the Patent Trial and Appeal Board (the "Board") highlights the different claim construction standards that are ordinarily applicable in post-grant review proceedings and in district court, and illustrates the Board's inclinations towards tactics that would alter the complexion of an inter partes review ("IPR") late in the proceedings.

In an IPR, "[a] claim in an unexpired patent shall be given its broadest reasonable construction in light of the specification of the patent in which it appears." 37 C.F.R. § 42.100(b) (emphasis added). The rationale for applying the broadest reasonable interpretation is that "patent owners have the opportunity to amend their claims during IPR, PGR, and CBM trials, unlike district court proceedings . . . ." Office Patent Trial Practice Guide, 74 Fed. Reg. 48756, 48764 (Aug. 14, 2012) ("PGR" refers to "Post-Grant Review" and "CBM" refers to "Covered Business Method"). In district court litigation, the words of a claim are given their ordinary and customary meaning, which is the meaning a term would have to a person of ordinary skill in the art at the time of the invention. See, e.g., Phillips v. AWH Corp., 415 F.3d 1303, 1312-13 (Fed. Cir. 2005).

Recently, just before an IPR's trial hearing (which is followed only by a final written decision), a patent owner sought to avoid the broadest reasonable interpretation standard by filing a terminal disclaimer, giving up the remainder of the patent's term. Amkor Tech., Inc. v. Tessera, Inc., IPR 2013-00242 (PTAB). The patent owner argued that because the petition and all of the petitioner's supporting evidence (including expert declarations) addressed the broadest reasonable interpretation standard rather than the now applicable district court standard, the IPR should be terminated for failure to present a prima facie case of invalidity. (See, e.g., Paper 121.)

In its decision, the Board stated that "[i]t is not feasible, at this late stage of the proceeding, to change the standard by which the challenged claims will be interpreted, as all of the arguments and evidence we have before us have applied the broadest reasonable interpretation standard. Changing the claim interpretation standard would require us, in essence, to start this inter partes review over again." (Paper 129, pp. 6-7.) To avoid what the Board perceived as potential "abuse" of the proceedings, the Board exercised its power to hold in abeyance the patent owner's terminal disclaimer until after the conclusion of the IPR (id., p. 6). See 37 C.F.R. § 42.7(b) ("The Board may vacate or hold in abeyance any non-Board action directed to a proceeding while an application or patent is under the jurisdiction of the Board unless the action was authorized by the Board."). Accordingly, the Board denied the patent owner's request to terminate and held that the broadest reasonable interpretation standard would continue to apply.

The Board, however, emphasized that the patent owner had the prior opportunity to seek to amend its claims, and that the "Patent Owner could have, for example, filed a terminal disclaimer with its Response had it wanted us to consider a different claim construction standard." (Paper 129, p. 10.) Notably, the involved patent was set to expire relatively soon, in December 2014.

Although the patent owner in this case may have simply wanted to terminate the IPR, there may ultimately be instances where a patent owner could benefit from the application of the district court claim construction standard, despite having to give up patent term via a terminal disclaimer. For example, at the time the IPR petition is filed, the involved patent may expire soon anyway, and the patent owner might wish to advocate in favor of a claim construction adopted in a prior litigation.

The outcome in this IPR is also useful to illustrate how the Board, under the pressure of a statutory deadline to complete IPRs, is disinclined to undo significant portions of the trial. Therefore, requests, for example, to apply an alternate claim construction standard should likely be made early in the proceedings.

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