Federal Circuit Clarifies Means-Plus-Function (Sort Of)

MIT v. Abacus Software (05-1142) - September 13, 2006

In what looked like an absolute mess of a case, MIT sued Abacus Software, Corel, Microsoft, Roxio and 200 other defendants in the Eastern District of Texas for allegedly infringing U.S. Patent 4,500,919 regarding a color processing system for producing copies of color originals. During litigation, the court issued a Markman order that was adverse to the patentee. After summary judgment was denied to both sides in the action, everyone stipulated to entry of final judgment of non-infringment of the ‘919 patent based on the Court’s claim construction, and took the case to the Federal Circuit on appeal.

At issue was claim 1:

1. A system for reproducing a color original in a medium using a selected multiplicity of reproduction colorants, the system comprising in serial order:

a.) a scanner for producing from said color original a set of three tristimulus appearance signals dependent on the colors in said original;

b.) display means connected to the scanner for receiving the appearance signals and aesthetic correction circuitry for interactively introducing aesthetically desired alterations into said appearance signals to produce modified appearance signals; and

c.) colorant selection mechanism for receiving said modified appearance signals and for selecting corresponding reproduction signals representing values of said reproducing colorants to produce in said medium a colorimetrically-matched reproduction.

The term "scanner" was at the center of a battle-of-the-textbooks spat since the term wasn't sufficiently defined in the specification. Turning to dictionaries, the Federal Circuit concluded that, to qualify as a "scanner" for the purposes of the '919 patent, the device must have "relative movement between the scanning element and the object being scanned."

The court also had to consider whether the "color original" that the scanner scans must be "placed on or in close proximity to the scanner." In this regard, neither the specification nor the dictionaries were of much help. Looking at the lower court's reliance on the ‘919 specification, expert testimony, and technical references, the Federal Circuit agreed that scanners require close proximity between the color original and the scanner.

MIT next argued that the district court erroneously held the phrase "colorant selection mechanism" as a means-plus-function limitation under section 112 ¶ 6. The phrase appears in the patent together with a description of its functions, "receiving said modified appearance signals" and "selecting corresponding reproduction signals representing values of said reproducing colorants to produce in said medium a colorimetrically-matched reproduction." The Federal Circuit concluded that, despite the lack of "means" language, the phrase "colorant selection mechanism" should be construed as a means-plus-function limitation:

The generic terms "mechanism," "means," "element," and "device," typically do not connote sufficiently definite structure. In Personalized Media Commc’ns, LLC v. Int’l Trade Com’n, 161 F.3d 696 (Fed. Cir. 1998), we addressed the claim term "digital detector." We contrasted the term "detector," which recited sufficient structure to avoid 112 ¶ 6, with "generic structural term[s] such as ‘means,’ ‘element,’ or ‘device,’" which do not. Id. at 704. Similarly, in Lighting World, Inc. v. Birchwood Lighting, Inc., 382 F.3d 1354 (Fed. Cir. 2004), we recognized that Section 112 ¶ 6 does not apply to "a term that is simply a nonce word or a verbal construct that is not recognized as the name of structure and is simply a substitute for the term ‘means for.’" Id. at 1360.

Here the patentee used "mechanism" and "means" as synonyms. See ‘919 patent,
claim 3, col. 15 l. 51 (referring to "colorant selection means") (emphasis added); id., claim 14, col. 17 ll. 1-2 (same). At least one dictionary definition equates mechanism with means. See The Random House Webster’s Unabridged Dictionary 1193 def. 2 (2d ed. 1998) (defining "mechanism" as "the agency or means by which an effect is produced or a purpose is accomplished") . . . The term "mechanism" standing alone connotes no more structure than the term "means."

[I]n contrast, the term "colorant selection," which modifies "mechanism" here, is not defined in the specification and has no dictionary definition, and there is no suggestion that it has a generally understood meaning in the art. We therefore agree with the district court that "colorant selection mechanism" does not connote sufficient structure to a person of ordinary skill in the art to avoid 112 ¶ 6 treatment

Next, the Federal Circuit considered whether the term "aesthetic correction circuitry" connotes sufficient structure to avoid 112 ¶ 6 treatment. The majority concluded that it did:

In contrast to the term "mechanism," dictionary definitions establish that the term "circuitry," by itself, connotes structure. Webster’s Third New International Dictionary, 408-09 (1968 ed.) (defining "circuit" as "the complete path of an electric current including any displacement current" and "circuitry" as "the detailed plan of an electric circuit or network (as of a radio or television receiver)"); see also Linear Tech. Corp. v. Impala Linear Corp., 379 F.3d 1311, 1320 (Fed. Cir. 2004) ("Technical dictionaries, which are evidence of the understandings of persons of skill in the technical arts, plainly indicate that the term ‘circuit’ connotes structure…

In two of our prior cases we concluded that the term "circuit," combined with a description of the function of the circuit, connoted sufficient structure to one of ordinary skill in the art to avoid 112 ¶ 6 treatment . . . The claim language here too does not merely describe a circuit; it adds further structure by describing the operation of the circuit. The circuit’s input is "appearance signals" produced by the scanner; its objective is to "interactively introduce[e] aesthetically desired alterations into said appearance signals"; and its output is "modified appearance signals." ‘919 patent, col. 15, ll. 29-41. This description of the operation of the circuit is sufficient to avoid 112 ¶ 6.

Chief Judge Michel dissented from this part of the claim construction, and provided a 14 page opinion, where 6 of those pages were spent explaining why "aesthetic correction circuitry" should be interpreted as a means-plus-function claim:

The district court correctly interpreted "aesthetic correction circuitry" as a means-plus-function claim despite the absence of the term "means for" in view of the presence of functional language because the limitation fails to recite sufficiently definite structure, as our precedent requires. Thus, the presumption against application of section 112, paragraph 6 was overcome. Indeed, on this record, I find it overcome as a matter of law.

The parties agree that "the term ‘circuit[ry],’ by itself connotes some structure" to one skilled in the art . . . The issue, however, is whether the "aesthetic correction circuitry" limitation "recite[s] sufficiently definite structure," . . . which is required to avoid section 112, paragraph 6 in a claim using functional language, even in the absence of "means for."

This "definite structure" requirement is well-established in our precedent. "To invoke this statute [section 112, paragraph 6], the alleged means-plus-function claim element must not recite a definite structure which performs the described function" . . . [W]e were shown no evidence that any technical dictionaries suggest to the artisan a sufficiently definite structure for "aesthetic correction circuitry" or even list such a term. Nor did experts from either side opine that one skilled in the art would understand "aesthetic correction circuitry" to connote sufficiently definite circuit structure.

VACATED-IN-PART, DISMISSED-IN-PART, and REMANDED

One interesting side-note about this case is that the court seems to be growing more impatient with parties taking liberties with the de novo standard of review. The opinion in this case made no secret of the court's discontent with increased requests to move earth, moon and sky every time claim contruction becomes an issue - you know you're in for a rough ride when the court opens the substantive part of the opinion with the following statement:

This case once again involves an effort by parties to a patent infringement case to have this court opine on a range of claim construction issues even though the judgment of the district court is not based on the resolution of those issues. We decline that invitation and limit our consideration to issues presented by the judgment under review. An appeal is not an opportunity to bring before the appellate court every ruling with which one of the parties disagrees without regard to whether the ruling has in any way impacted the final judgment. The fact that this is a patent case does not invoke a different legal regime.