United States: Amici Curiae to Federal Circuit: Patent Specification and Prosecution History, Rather than Dictionaries, Should Serve as the Primary Source for Claim Interpretation

On July 21, 2004, the Federal Circuit issued an order granting a petition to rehear en banc the appeal in Phillips v. AWH. The court "determined to hear this case en banc in order to resolve issues concerning the construction of patent claims," and invited the parties as well as amicus curiae to submit briefs on seven very specific questions relating to claim construction methodology and review on appeal. The response to the court’s call for amicus briefs was indicative of the keen interest in the bar on these issues. Thirty-three responses were filed, with the majority of them urging the court to interpret claim terms by looking primarily to the patentee’s use of the terms in the specification and prosecution history and secondarily to dictionaries and similar sources if useful. The majority of the amici also advocated allowing expert testimony to play at least some role in claim construction. Further, most of the amici that addressed the final question posed in Phillips urged the Federal Circuit to accord deference to varying aspects of trial court claim construction rulings, rather than review these findings entirely de novo.

The majority of amici responded to this question by arguing that the public notice function of patent claims is best served by referencing primarily to the patentee’s use of the term in the specification. Indeed, twenty-four of the thirty-three amici subscribed to this view. A consensus voiced by the amici is that looking primarily to the specification, rather than dictionaries, best reflects how a person of ordinary skill in the art would determine the meaning of a disputed claim term at the time of the patent application. Many amici criticized dictionaries for being unduly malleable. The amici explained that a court or litigant can have its pick of 72,785 readily-available dictionaries. Some amici pointed out that dictionaries can lag woefully behind the pace of innovation, leading to unpredictable claim construction results. Other amici noted that the Federal Circuit has employed twenty-four different general purpose dictionaries to perform claim construction in the last decade. The U.S. PTO explained that use of dictionary definitions has resulted in litigants converting claim construction disputes into what the PTO characterized as a "battle of dictionaries." The PTO argued that the "increased reliance on dictionaries as a foundation for claim meaning has generated inconsistent and unpredictable results, and therefore has not improved the state of the law of claim construction."

Four of the thirty-three amici argued that dictionaries should enjoy primacy. These amici expressed concern that favoring the specification would unnecessarily narrow claim terms. Some found support for emphasizing dictionaries in the patent statute, 35 U.S.C. § 112, which, they noted, does not require the patentee to set forth all relevant definitions. Other amici maintained that dictionaries are widely available, are authored by neutral parties, and place a premium on accurately reflecting consensus about what particular words mean at a given time.

Still other amici advocated nuanced, context-specific approaches. These parties attacked the propriety of distilling meaning from a single source. The Federal Circuit Bar Association, for example, argued that a mechanical approach is impracticable given the vast range of claim construction issues. Similarly, other amici opined that a person of ordinary skill in the art would look both to the specification and to dictionaries to understand a claim term. However, such methodologies drew fire from other amici, who argued that this approach would shift the key inquiry from a patentee’s drafting choices to an ad-hoc, totality-of-the-circumstances assessment by a judge.

Phillips Question No. 2 for Amici Curiae

This question generated a comparatively sparse response, perhaps because few amici accepted the threshold proposition that dictionaries should serve as the primary source for claim interpretation.

Most amici that answered Question No. 1 in the affirmative — advocating that dictionaries should serve as the primary source for claim construction — contended that the specification should limit the scope of claim language only in two circumstances, namely when the patentee has acted as his own lexicographer or the specification reflects a clear disclaimer of claim scope. There was limited discussion among the amici of what language in the specification or prosecution history should be sufficient to limit the scope of a claim.

The amici split on whether courts should favor general or technical dictionaries. Several amici preferred technical dictionaries, arguing that one of ordinary skill in the art would more likely consult specialized or scientific sources. Others argued that the two types of dictionaries should carry equal weight or that the choice should hinge on whether the disputed term was "general" or "technical."

Finally, most amici opined that it was appropriate to look to the specification if the dictionaries provide multiple potentially applicable definitions of a term. Some argued that considering the specification should be mandatory in such circumstances. Others explained that doing so would restrict the number of definitions upon which each side could rely.

Although amici generally agreed that courts should consult dictionaries if the specification is not dispositive, some remained ambivalent about the prospect of consulting dictionaries at all. Some contended that dictionaries should be vetted to make sure that they provide relevant, technically-accurate information.

Seven of the eight amici that addressed the issue agreed that the range of the ordinary meaning of claim language should not be limited to the scope of the invention disclosed in the specification when only a single embodiment, and no other indication of breadth, is disclosed. At least one trade association brief argued that limiting the range of claim language in this manner would increase the size and cost of patent applications.

The amici who addressed this issue unanimously rejected the concept of harmonizing the claim construction methodologies of the majority and dissent in this manner. Some amici argued that the proposed dual methodology would add another layer of complexity to claim construction, undermining a chief objective of the public notice function: creating predictable results. Other amici commented that the dual methodology would be inconsistent with how a person of ordinary skill in the art would view the meaning of a claim term. Still other amici contended that the proposed dual methodology would be too onerous and thus would chill the issuance of patents.

Twenty-two of the thirty-three amici addressed this question. Among these amici, there was a clear consensus against a general rule mandating courts to construe claim language narrowly to preserve validity. Only four amici were in favor of such a blanket rule. The rest of the amici contended to varying degrees that courts should not narrowly construe claim language to avoid invalidity.

Eight amici argued against taking validity into account at all during claim construction. These amici maintained that permitting the court to take validity into consideration during claim construction improperly removed the validity question from the jury, making validity essentially moot during a jury trial. Another eight amici argued against generally construing claim language narrowly to preserve validity. These amici encouraged the Federal Circuit to authorize a narrow construction only when two equally possible interpretations of a claim existed, and one interpretation would render the claim invalid, while the other would preserve its validity. The remaining two amici distinguished between newly discovered prior art and art of record. They asserted that, because the PTO had allowed the claims over the prior art of record, the claims should be construed to avoid such art. But for prior art that the PTO had not considered, there would be no basis for narrowly construing the claims to avoid that art.

Thirty of the amici addressed at least some portion of this question, and there was a consensus regarding the role of prosecution history in construing the claims. Twenty-seven amici stated that the prosecution history was a primary source of intrinsic evidence that courts should use along with the specification to interpret claim terms. The amici split, however, on the specific role the file history should play. While twenty-one amici thought that the file history should be consulted on the same level as the specification, eight felt that it should only be consulted to see whether the applicant disavowed claim scope, or that it should not be permitted to enlarge claim scope.

There was no clear consensus among amici regarding the use of expert testimony, although a majority (twenty-four) argued that experts should play some role during claim construction. Among those in favor of using experts, seven argued that expert testimony should be used so long as it does not contradict the intrinsic evidence. Six advocated using experts to educate the court on the subject technology and on how a person of ordinary skill would interpret terms. Seven favored using experts only where there clearly was an ambiguity in the claim language, and six cautioned that courts must scrutinize expert testimony for bias. Five amici argued that expert testimony must always be allowed because claim construction should focus on one of ordinary skill in the art, and only an expert can provide that perspective.

Phillips Question No. 7 for Amici Curiae

This was the only question that did not address claim construction methodology on the merits. Instead, question seven focused on whether and to what extent the Federal Circuit should accord deference to a trial court’s claim construction. Twenty-three of the thirty-three amici responded to at least some part of this question.

On the bottom-line question of whether the Federal Circuit should defer, there was a clear consensus. Seventeen amici urged the Federal Circuit to defer on at least certain aspects of a trial court claim construction, while only two amici argued that there should be no deference. Four amici did not provide a direct answer. Some of the amici in the majority maintained that the Federal Circuit should only defer on very limited issues such as, for example, when the trial court had heard live witnesses and potentially made credibility determinations. Other amici thought the deference should be far more sweeping. These amici contended that deference should apply to findings such as the level of ordinary skill in the art, the scope and content of the prior art, whether the applicant had acted as a lexicographer or expressly disavowed claim scope, the best tools to use in construing terms, the qualifications of a person of ordinary skill, what materials one skilled in the art would look at in construing claim language, and how one skilled in the art would understand claim terms and statements in prosecution.

There was also a clear majority on the question of whether according deference would be consistent with the Supreme Court’s Markman decision. On that question, eleven amici stated that deferring would be consistent with Markman, while only two thought that it would be inconsistent. There was again a clear majority—although in the opposite direction—in answer to the question of whether it would be consistent with the Cybor case to accord deference. On that question, eleven amici stated that deference would be inconsistent with Cybor. None argued that granting deference would be consistent with Cybor.

These responses suggest that there is a groundswell of support among members of the patent bar for the Federal Circuit to accord some deference to trial court claim constructions. Based on the submissions, however, the Phillips en banc court would probably need to overrule the prior en banc decision in Cybor.

Because of the generality of this update, the information provided herein may not be applicable in all situations and should not be acted upon without specific legal advice based on particular situations.

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