Brief Fact Summary. Phillips (Plaintiff), who sued AWH Corp. (Defendant) for patent infringement, argued that the term â€œbafflesâ€ in claim 1 of his patented invention (the â€˜798 patent) was not used in a restrictive manner in order to exclude structures that extend at a 90-degree angle from walls, and that the term should be given its plain meaning, rather than limiting the term to corresponding structures disclosed in the patent’s specification, or their equivalents.
Synopsis of Rule of Law. A term in a claim of a patented invention should not be restricted to corresponding structures disclosed in the specification, or their equivalents, where the term’s plain meaning can be used without such limitation.
Should a term in a claim of a patented invention be restricted to corresponding structures disclosed in the specification, or their equivalents, where the term’s plain meaning can be used without such limitation?
Held. (Bryson, J.) No. A term in a claim of a patented invention should not be restricted to corresponding structures disclosed in the specification, or their equivalents, where the term’s plain meaning can be used without such limitation. The issue of claim interpretation is framed by Â§ 112 of the Patent Act (35 U.S.C. Â§ 112). The second paragraph of that section tells the court to look to the language of the claims to determine what â€œthe applicant regards as his invention.â€ On the other hand, the first paragraph requires that the specification describe the invention set forth in the claims. The main question presented, therefore, is how much the court should resort to and rely on a patent’s specification in seeking to determine the proper scope of its claims. First, it is a â€œbedrock principleâ€ of patent law that â€œthe claims of a patent define the invention to which the patentee is entitled the right to exclude.â€ In addition, the words of a claim are given their ordinary and customary meaning, which is the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention. Importantly, the person of ordinary skill in the art is deemed to read the claim term not only in the context of the particular claim in which the disputed term appears, but in the context of the entire patent, including the specification. Where the ordinary meaning of claim language is readily obvious even to lay judges, general application dictionaries may be helpful. However, where such meaning is not apparent, the court must look to those sources available to the public that show what a person of skill in the art would have understood disputed claim language to mean. Those sources include the words of the claims themselves, the remainder of the specification, the history of prosecution, and extrinsic evidence concerning relevant scientific principles, the meaning of technical terms, and the state of the art. Claims must be read in view of the specifications of which they are a part. Extrinsic evidence may include technical dictionaries and experts. However, an approach of claim language construction that places greater emphasis on technical dictionaries and encyclopedias than on the specification and prosecution history is inconsistent with rulings that the specification is the single best guide to the meaning of the disputed term and that the specification acts as a dictionary when it expressly defines terms used in the claims or when it defines terms by implication. The main problem with elevating the dictionary to such prominence is that it focuses the inquiry on the abstract meaning of words rather than on the meaning of claim terms within the context of the patent. Properly viewed, the â€œordinary meaningâ€ of a claim term is its meaning to the ordinary artisan after reading the entire patent. The problem is that if the district court starts with the broad dictionary definition in every case and fails to fully appreciate how the specification implicitly limits that definition, the error will systematically cause the construction of the claim to be overly expansive. The risk of systematic overbreadth is greatly reduced if the court focuses at the beginning on how the patentee used the claim term in the claims, specification, and prosecution history, rather than starting with a broad definition and whittling it down. In cases where it will be hard to determine whether a person of skill in the art would understand the embodiments to define the outer limits of the claim term or merely to be exemplary in nature, attempting to resolve that problem in the context of the particular patent is likely to capture the scope of the actual invention more accurately than either strictly limiting the scope of the claims to the embodiments disclosed in the specification or divorcing the claim language from the specification. Applying these principles, it is clear from claim 1 that the baffles must be made of steel, must be a part of the load-bearing means for the wall section, and must be pointed inward from the walls. Both parties stipulate that â€œbafflesâ€ refers to objects that check, impede, or obstruct the flow of something. The other claims of the’798 patent and the specification support the conclusion that persons of ordinary skill in the art would understand the baffles recited in the patent to be load-bearing objects that serve to check, impede, or obstruct flow. At several points, the specification discusses positioning the baffles in order to block projectiles. While the patent makes clear the invention envisions baffles that serve that function, it does not imply that in order to qualify as baffles within the meaning of the claims, the internal support structures must serve the projectile-deflecting function in all the embodiments of all the claims. The specification includes several other purposes served by the baffles, e.g., providing structural support. The specification also provides for â€œoverlapping and interlocking the baffles to produce substantially an intermediate barrier wall between the opposite [wall] facesâ€ to create insulation compartments. The fact that the written description of the â€˜798 patent sets forth many objectives to be served by the baffles recited in the claims confirms that the term â€œbafflesâ€ should not be read restrictively to require that the baffles in each case serve all of the recited functions. In this case, although deflecting projectiles is one of the advantages of the baffles, the patent does not require that the inward extending structures always be capable of performing that function. Accordingly, a person of skill in the art would not interpret the disclosure and claims of the â€˜798 patent to mean that a structure extending inward from one of the wall faces is a â€œbaffleâ€ if it is at an acute or obtuse angle, but is not a â€œbaffleâ€ if it is disposed at a right angle. Remanded.
Dissent. (Mayer, J.) It is pointless to conceive of claim construction as a matter of law lacking any factual components. Instead, claim construction is, or should be, made in context: a claim should be interpreted both from the perspective of one of ordinary skill in the art and in view of the state of the art at the time of invention. These questions, which are critical to the correct interpretation of a claim, are inherently factual. They are hotly contested by the parties, not by resort to case law as one would expect for legal issues, but based on testimony and documentary evidence. Otherwise, by trying to arrive at a conclusion from a purely legal view in the court of appeals, as the majority has done, and by not deferring to the district court’s factual findings, â€œthere is no reason why litigants should be required to parade their evidence before the district courts or for the district courts to waste time and resources evaluating such evidence.â€
Discussion. The effect of this case has been to limit exclusive reliance on dictionaries as an â€œobjectiveâ€ and presumptive source for meanings of claim terms. After Phillips, courts may still use dictionaries in conjunction with the specification, especially where there is no intrinsic evidence in the specification as to a term’s specialized meaning, but the specification must be referenced to the extent possible.