In his novel My Summer in a Garden (1870), Charles Dudley Warner famously said "Politics makes strange bedfellows."  That aphorism is illustrated once again in the joining of the Public Patent Foundation with eight technology transfer organizations and the Association of University of Technology Managers,* urging the Federal Circuit to overturn its decision in Cybor Corp. v. FAS Technologies, Inc., 138 F.3d 1448, 1456 (Fed. Cir. 1998) (en banc), that claim construction by a district court is entitled to no deference.

The brief (~7 page) amicus brief addresses the three questions posed by the Federal Circuit for en banc review:

1) Should [the] court overrule Cybor []?

2) Should [the] court afford deference to any aspect of a district court's claim construction?

3) If so, which aspects should be afforded deference?

As to the first question, the brief answers in the affirmative, simply stating that Cybor should be overruled to the extent it places factual determinations "outside the realm of deferential review" for reasons set forth in the remainder of the brief.

Regarding the second question, the brief notes that claim construction is a mixed question of law and fact, a situation not unusual in patent law, citing obviousness and enablement as being questions of law based on frequently disputed facts.  A district court's factual determination relating to these questions is reviewed under a "substantial evidence" standard (e.g., Martek Biosciences Corp. v. Nutrinova, Inc., 579 F.3d 1363, 1378 (Fed. Cir. 2009) (enablement); Honeywell Int'l, Inc. v. United States, 609 F.3d 1292, 1297 (Fed. Cir. 2010) (obviousness).  The brief also notes that the Supreme Court's decision in Markman v. Westview Instruments does not mandate the approach taken by the Federal Circuit in Cybor.  Even certain members of the Court (former Chief Judge Michel, current Chief Judge Rader) don't agree with the Court's approach in Cybor:

It seems to me that the claim construction question often cannot be answered without assessing, at least implicitly, what the average artisan knew and how she thought about the particular technology when the patent claims were written.  To make such determinations, the trial judge necessarily relies upon prior art documents and other evidence concerning the skill of the ordinary artisan at the relevant time.  Indeed, trial judges are arguably better equipped than appellate judges to make these factual determinations, especially in close cases.  In such instances, perhaps we should routinely give at least some deference to the trial court, given its greater knowledge of the facts.

Amgen Inc. v. Hoechst Marion Roussel, Inc., 469 F.3d 1039, 1041 (Fed. Cir. 2006) (Michel, C.J. and Rader, J., dissenting).

And other members of the Court have gone further, citing Fed. R. Civ. Pro. Rule 52(a); see Phillips v. AWH Corp., 415 F.3d 1303, 1332 (Fed. Cir. 2005) (en banc) (Mayer, J., and Newman, J., dissenting).  The TTO's amicus brief states:

The Amici agree with these dissenting opinions -- there is no reason to treat the appellate review of factual underpinnings related to claim construction any differently than any other factual determinations.  The resulting deference will ensure a greater predictability for the claim construction proceeding, and will avoid having to "re-try" the factual underpinnings of claim construction on appeal.

The advantages of adopting this standard of review would include "a greater predictability for the claim construction proceeding" and "avoid[ing] having to 're-try' the factual underpinnings of claim construction on appeal."  The resulting "[p]redictability and avoidance of duplicative effort are of particular importance to universities, related institutions, and the organizations to which such institutions belong," according to the brief, "particularly since patent litigation, with its attendant costs and uncertain outcome already places such institutions in a disadvantaged position."

Finally, the brief argues that a district court's factual determinations incident to claim construction should be reviewed under a "substantial evidence" standard.  The brief illustrates the consequences and justifications of their approach using the case at bar:

In resolving this question [i.e., the meaning of a disputed claim term], the district court evaluated evidence in the form of expert deposition testimony (and the parties' arguments thereon) regarding how persons skilled in the art would understand the limitation[].  After such evaluation, the district court found that such limitation indeed "corresponds to a class of structures."

The district court's finding regarding the meaning of [the disputed claim term] to those of ordinary skill in the art was indisputably one of fact.  The subject patent itself contained no evidence of how such hypothetical persons would understand that term, and the parties were consequently required to rely upon extrinsic evidence in the form of expert depositions in order to support their respective positions on the subject.  As with any other factual finding regarding claim construction, this factual finding is entitled to deference in the appellate review thereof.

One relevant argument in favor of discarding the claim construction analysis from Cybor is that in so doing the Federal Circuit might avoid the high percentage of reversals of district court claim construction (~30-40% according to some legal academics).  The counter-argument is that often, and perhaps the majority of the time, a district court's factual determinations can be dispositive of the claim construction exercise.  In these circumstances, giving even a "substantial evidence" level of deferential review to these factual determinations may vitiate any de novo review by the Federal Circuit of how the claims are properly construed as a matter of law.

The Federal Circuit is scheduled to hear the appeal en banc on September 13, 2013.

* The amici are: Association of University Technology Managers (AUTM), NUtech Ventures, Inc. (University of Nebraska – Lincoln), UNeMED Corporation (University of Nebraska Medical Center), STC.UNM (University of New Mexico), Wisconsin Alumni Research Foundation (University of Wisconsin), Colorado State University Research Foundation, Public Patent Foundation, Tec Edmonton (University of Alberta and City of Edmonton), The University of Pittsburgh of The Commonwealth System of Higher of Education, and Newsouth Innovations (University of New South Wales, Australia)

Hat tip to Gray on Claims for providing the amicus brief