Same claim term can be interpreted differently in the same claim if specification warrantsApril 9, 2008

In a decision last week, the Federal Circuit decided a case addressing the limitations of what constitutes "insolubly ambiguous" claim terms in order to amount to indefiniteness. The district court held the asserted claims invalid because they impermissibly mixed two statutory classes of subject matter, as well as because they required construing the same term differently in the same claim for the claims to make sense.The Federal Circuit reversed the invalidity holding, finding that while the claims were written in an "unconventional" format, that format did not result in mixing multiple classes of statutory subject matter in the same claim. Further, while the court acknowledged that typically the same term is given the same construction throughout a claim (particularly when the second instance is prefaced with "the" or "said," thereby making reference to the first use), in this case, there was no "uniform language" surrounding the term that mandated an identical construction, and as a result, the claim was not indefinite.Not all was good for the patentee, however, as the court affirmed the district court's claim construction. The patentee stipulated that if the claim construction was affirmed, there was no infringement, and as a result, the district court's summary judgment of noninfringement was affirmed. More detail of Microprocessor Enhancement Corp. v. Texas Instruments, Inc. after the jump.Plaintiff Microprocessor Enhancement Corp. (MEC) brought suit against both Texas Instruments (TI) and Intel Corp. for infringement of method and apparatus claims of its microprocessor enhancement patent. The suit against Intel was separated from the suit against TI. In its suit, TI moved for summary judgment of invalidity and noninfringement. Intel also moved for summary judgment of noninfringement. The TI court found that the patent impermissibly mixed two classes of patentable subject matter in claim 1 (a method claim) and claim 7 (an apparatus claim) and that the claims required a single word to be interpreted differently in different parts of a single claim. The TI court also granted summary judgment of noninfringement by construing the terms "pipeline stage" and "instruction execution pipeline stage." After the TI court indicated that summary judgment would be granted, Intel and MEC stipulated for final adjudication. They explicitly recognized that MEC would be collaterally estopped from challenging the TI invalidity ruling, recognized the TI claim construction would be applicable to further proceedings, and submitted additional evidence. MEC then appealed both cases and later moved to consolidate the appeals, which the clerk granted. On appeal, TI argued first that the two cases were not properly consolidated because the additional evidence submitted upon Intel and MEC's stipulation had not been admitted by the TI court. Generally, evidence not admitted by a district court can not be part of the records on appeal. But, the Federal Circuit found that the additional evidence didn't contradict the other evidence on record, and therefore the additional evidence would not change its determination.Turning to the indefiniteness argument, the court noted that claims are presumed valid and will only be indefinite "if the claim is insolubly ambiguous, and no narrowing construction can properly be adopted." The district court had found that the claims were insolubly ambiguous because (1) claim 1 incorporated a preamble within a preamble structure, thus evidencing an intent to claim the apparatus as well as a method, and (2) claim 7 included functional limitations directed to the use of the apparatus, making it a method claim as well as an apparatus claim. The Federal Circuit disagreed, finding that a preamble within a preamble structure simply limited the practicing of the claimed method in an processor with the requisite structure. Further, the court noted that apparatus claims like that of claim 7 are not necessarily indefinite for using functional language, finding that claim 7 was "clearly limited" to a recited structure that was capable of performing the recited functions. Lastly, the court found that claims 1 and 7 were not insolubly ambiguous in the use of a single term with different meanings throughout the claims. The court held that while a single claim term should typically be construed consistently in all places in the same claim, the "patentee's mere use of a term with an antecedent does not require that both terms have the same meaning." In this case, the term at issue was not surrounded by uniform language that would require a single interpretation and that the claims would be "nonsensical" if the term was not allowed to have different meanings. The Federal Circuit next addressed the district court's interpretation of "pipeline stage" on de novo review. The district court applied a temporal construction to the term when it was used both with a modifier and without a modifier. MEC argued that a positional, not temporal, construction should apply to the unmodified uses, but the court did not agree. Following the Phillips hierarchy of claim construction, the court first evaluated the claim language itself and found that the terms surrounding the "pipeline stage" were also temporal in nature. However, the court was unable to determine whether a person of ordinary skill in the art would read the term as exclusively temporal from the specification. The court then looked at amendments in the prosecution history to determine that the inventor intended that the unmodified use have the same temporal sense as the modified uses. Specifically, the addition of the unmodified term during prosecution indicated the "applicant's intent that the term takes its antecedent basis, and thereby the function and temporal meaning from the previously used term." The court also looked at the parent application of the patent and found more evidence that the term was intended to be used in a temporal sense. Lastly, the court found that extrinsic evidence from a 1990 article supported the proposition that the unmodified version was a temporal term. Because MEC agreed that no infringement exists if the district court's claim construction stood, the court did not address the construction of "instruction execution pipeline stage" and affirmed the judgment of noninfringement.To read the full decision in Microprocessor Enhancement Corp. v. Texas Instruments, Inc., click here.

← Return to Filewrapper

Stay in Touch

Receive the latest news and updates from us and our attorneys.

Sign Up