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Patent Was Not Indefinite Under the Correct Claim Construction and Was Not Invalid for Failing to Satisfy the Best Mode Requirement Because the Alleged Undisclosed Best Mode Fell Outside the Scope of the Claim

06-1440
October 12, 2007
Kabakoff, Stephen E.

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Last Month at the Federal Circuit - November 2007

Judges: Newman, Rader (author), Gajarsa

[Appealed from: S.D. Tex., Judge Ellison]

In AllVoice Computing PLC v. Nuance Communications, Inc., No. 06-1440 (Fed. Cir. Oct. 12, 2007), the Federal Circuit reversed the district court’s grant of SJ in favor of Nuance Communications, Inc. (“Nuance”) that AllVoice Computing PLC’s (“AllVoice”) U.S. Patent No. 5,799,273 (“the ’273 patent”) was invalid as indefinite and for failure to satisfy best mode.

The ’273 patent is directed to voice recognition technology and covers an interface between a speech recognition engine and various end-user application programs on a personal computer. AllVoice alleged that Nuance’s Dragon Naturally Speaking software infringed the ’273 patent. On SJ, the district court held that the ’273 patent was invalid because claims 60, 61, and 67 were indefinite under 35 U.S.C. § 112, ¶ 2, and because the specification did not disclose the best mode of practicing claim 73. AllVoice appealed.

On appeal, the Federal Circuit disagreed with the district court and concluded that certain means-plusfunction limitations in claims 60, 61, and 67 satisfied the definiteness requirement. In so concluding, the Court observed that the test for definiteness asks whether one skilled in the art would understand the bounds of the claim when read in light of the specification. However, the district court did not specify the proficiency of the hypothetical person of ordinary skill in the art. The Court noted that during oral argument, AllVoice’s counsel defined a person of ordinary skill in the art in the context of this case as “someone who has a degree in computer science or something equivalent and 2-3 years experience programming in Windows” and that this definition was consistent with the level of skill ascertained in other software patent disputes. Slip op. at 5. Because Nuance did not pose a different definition nor dispute AllVoice’s definition, the Federal Circuit used AllVoice’s definition in applying the definiteness test. The Federal Circuit determined that the disputed limitations in claims 60, 61, and 67 are means-plusfunction elements under 35 U.S.C. § 112, ¶ 6. The Court noted that under 35 U.S.C. § 112, ¶¶ 2 and 6, a means-plus-function limitation is indefinite if a person of ordinary skill in the art would be unable to recognize the structure in the specification and associate it with thecorresponding function in the claim.

Claim 60 recited “output means for outputting the recognized words into at least any one of the plurality of different computer-related applications to allow processing of the recognised words as input text.” Id. at 6. Disagreeing with the district court’s construction that “this limitation require[d] a system outputting, alternately, to a plurality of different word processing or other application programs,” the Federal Circuit noted that the district court improperly added the requirement that the system be able to output “alternately” to different programs. Id. The Court reasoned that although the output means must be capable of outputting recognized words to more than one program, the claim did not suggest the requirement that the means do so alternately. In other words, noted the Court, the district court incorrectly added the requirement that the user have the ability to change the destination program “on the fly.” The Court concluded that a person skilled in the art would understand the clause to merely require compatibility with multiple output programs, not the ability of users to switch between multiple output programs at will.

Viewing the prosecution history in proper context, the Court construed claim 60 to require “a system capable of outputting to a plurality of different word processing or other application programs.” Id. at 7. Under this construction, the Court held that the specification did contain structure corresponding to the “output means” clause of claim 60 and that the record showed that an artisan of ordinary skill would understand the bounds of the claim when read in light of the specification. Accordingly, the Court concluded that claim 60 satisfied the definiteness requirement.

With respect to claims 61 and 67, the Federal Circuit noted that the claim terms at issue related to the interface’s ability to perform functions “independent of” the connected application program. The district court construed “independent of” to mean essentially “isolated.” Id. at 9. The Federal Circuit noted that according to this interpretation, the claimed interface could not receive any information from the application and that it must keep track of the positions of words in the application without ever obtaining position data from the application. The Federal Circuit rejected this interpretation and concluded that the claim term “independent of” meant that “the interface must maintain its own position data, in its own data structures, but still have the ability to receive positional information from the application.” Id. In so concluding, the Court noted that “[o]nce again the district court went astray by taking the prosecution history out of context.” Id. The Federal Circuit observed that with a proper reading of the claim term, the specification did contain adequate structure. It concluded that because neither the claim language nor the prosecution required more, the district court erred in finding claims 61 and 67 indefinite on the basis of the “independent of” language.

The Federal Circuit also disagreed with the district court’s conclusion that claims 61 and 67 were indefinite for failure to set forth sufficient algorithmic structure associated with the disputed means-plus-function limitations. The Court found that the specification contained sufficient algorithmic structure to give meaning to claims 61 and 67. It observed that claim definiteness depends on the skill level of a person of ordinary skill in the art and that “[i]n software cases, therefore, algorithms in the specification need only disclose adequate defining structure to render the bounds of the claim understandable to one of ordinary skill in the art.” Id. at 12. The Court noted, relying on the statement of AllVoice’s expert, that the record did contain sufficient algorithmic structure to give meaning to the claim terms. Accordingly, it held that claims 61 and 67 satisfied the definiteness requirement.

The Federal Circuit next turned to the district court’s grant of SJ of invalidity based on best mode of claim 73 of the ’273 patent, which recites instructions for performing a variety of functions and includes, inter alia, an instruction for “causing the processor to implement the interface application program to form link data linking the audio data to the recognised words, . . . .” Id. at 3. The Federal Circuit noted that the invention in claim 73, essentially a data link, keeps track of word position changes to identify audio corresponding with the selected text. The district court held that claim 73 of the ’273 patent was invalid for deliberate concealment of the best mode, a requirement of U.S.C. § 112, ¶ 1. The Federal Circuit disagreed, concluding that a careful reading of claim 73 showed that the alleged undisclosed best mode was not a best mode of practicing the claimed invention and that the alleged best mode subject matter fell outside the scope of claim 73.

The Federal Circuit observed that the best mode requirement “ensures [that] a patent applicant discloses the preferred embodiment of his invention” and that only the claimed invention is subject to the best mode requirement. Id. at 14. The Court noted that to apply the best mode standard, a court must first determine whether, at the time the patent application was filed, the inventor had a best mode of practicing the claimed invention. This determination, stated the Court, turns on the inventor’s own subjective beliefs.

The Federal Circuit observed that Nuance alleged, and the district court agreed, that some functions of WordExpress, one of AllVoice’s commercial products, constituted an undisclosed best mode for claim 73. In reaching this judgment, the district court assumed that claim 73 required maintaining or updating link data during the editing process. Based on this assumption, the district court held that the best mode for maintaining links after editing included a certain software “macro,” Microsoft Windows “hooks,” and the disabling of certain features of Microsoft Word. Id.

The Federal Circuit found that the district court incorrectly held that the macro’s functions were within the scope of claim 73. In light of the specification as a whole and the claim language, the Federal Circuit construed “form[ing] link data” in claim 73 as “the formation of the data structure in volatile memory, excluding operations to update or maintain link accuracy.” Id. at 16.

Unlike claims 1, 15, and 28, and others in the ’273 patent, claim 73 did not include “updating” link data, “maintaining” link data after editing, or “monitoring” changes to text. Id. at 18. The Federal Circuit concluded that because “forming link data” did not include monitoring changes or updating link data, a method to perform those unclaimed functions fell outside the scope of claim 73. It observed that the macro considered by the district court did nothing more than monitor the changes to a document, to eventually facilitate the updating of link data. Because claim 73 did not include these features, the macro could not be a best mode for claim 73. Because the alleged best mode did not fall within the scope of claim 73, the Court did not consider whether the inventors of the ’273 patent actually believed the macro was their best mode of practicing the invention or whether they deliberately concealed that subject matter.

Nuance argued that claim 73 implicitly included “updating” or “maintaining” link data. The Federal Circuit also rejected this argument, noting that each claim need not include every feature of an invention and that it enforces a presumption that each claim in a patent has a different scope. Because the functionality of the alleged best mode fell outside the scope of claim 73, the Court found no violation of the best mode and reversed the district court’s holding of invalidity of the ’273 patent.