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CAFC Creates Potential Conflict in De Nove Review of MPF Claims

By Peter Zura

Aristocrat Tech. v. Multimedia Games, Inc. (2007-1375), February 22, 2008, Non-Precedential

Aristocrat appealed the order from the Central District of California entering summary judgment of invalidity for indefiniteness of their patent. Multimedia filed a motion for summary judgment arguing that a disputed claim was invalid for indefiniteness, because the specification of the patent failed to disclose necessary structure corresponding to several of the means-plus-function limitations. The district court agreed with Multimedia and concluded that the claims were invalid as indefinite.

One of the disputes surrounded the construction of "control means." Aristocrat argued that the term as claimed was not in means-plus-function (MPF), because one skilled in the art would recognize it as a processor, and because the "subsidiary" limitations (e.g., memory, programming, etc.) together provided enough structure to escape 112, paragraph 6. The CAFC disagreed, but added:

[W]e do not agree with the apparent argument by Multimedia that subsidiary means-plus-function limitations can never define sufficient structure to rebut the presumption concerning means-plus-function treatment of a parent clause on the ground that they only recite additional functions . . .The structure of a parent means clause must be disclosed in terms of the functions that the claim states the means performs. Here, it is not clear that the structures allegedly associated with the subsidiary means as a whole are capable of performing all of the functions associated with the parent means. However, under different circumstances it may be possible that once identified, structures corresponding to the subsidiary means-plus-function limitations may as a whole sufficiently recite the structure for performing the superior function such that resort to the specification for further corresponding structure is not necessary. Because that is not the case here, we conclude that the presumption of means-plus-function treatment applies, and "control means" should be construed as a means-plus-function limitation subject to having structural support in the specification.

Identifying the claims as MPF, the CAFC then concluded that additional factual determinations were needed to properly construe the claims

We conclude that genuine issues of material fact exist concerning whether one skilled in the art of computer programming would identify structure in the specification associated with the various asserted claim limitations, thereby precluding summary judgment, and we thus reverse the district court?s summary judgment order.

What's the big deal?

In Chiuminatta Concrete Concepts, Inc. v. Cardinal Industries, Inc., 145 F.3d 1303 (Fed. Cir. 1998), the CAFC held that MPF claim construction is a legal matter, subject to de novo review under Cybor:

A determination of the claimed function, being a matter of construction of specific terms in the claim, is a question of law, reviewed de novo. See Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448 (Fed.Cir.1998) (en banc); Markman v. Westview Instruments, Inc., 52 F.3d 967, 979 (Fed.Cir.1995) (en banc), aff'd, 517 U.S. 370 (1996).?

This would explain why the opinion was issued as nonprecedential. But the implication seems clear: the rethinking of Cybor de novo review may well be underway.

See Hal Wegner's article "Rethinking Cybor De Novo Review: Inherent Factual Determinations" (link)

Full post as published by Two-Seventy-One Patent Blog on February 25, 2008 (boomark / email).