Phillips v. AWH Corporation

Brief Fact Summary.

Phillips (Plaintiff) sued AWH Corp. (Defendant) for patent infringement, and contended that the term “baffles” in claim 1 of his patented invention (the ‘798 patent) was not used in a restrictive manner that would exclude structures that extend at a 90-degree angle from walls, and that the plain meaning should be given to the term, 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, when the plain meaning of the term can be used without causing the limitation.

Facts.

Plaintiff invented, and obtained a patent on, modular, steel-shell panels that could be welded together to form walls resistant to vandalism.  Plaintiff sued Defendant for patent infringement.  Claim 1 of his patent (the ‘798 patent) stated: “further means disposed inside the shell for increasing its load bearing capacity comprising internal steel baffles extending inwardly from the steel shell walls.”  The district court found that the accused infringing product did not contain “baffles” as that term was used in Claim 1, and therefore, granted summary judgment of noninfringement.  On appeal, the original court of appeals panel concluded that the term “baffles” was used in a restrictive manner in the patent which excluded structures that extend at a 90-degree angle from the walls.  That panel noted that the specification repeatedly referred to the ability of the claimed baffles to deflect projectiles and that it described the baffles as being “disposed at such angles that bullets which might penetrate the outer steel panels are deflected.”  The panel also noted that nowhere did the patent disclose a right-angle baffle, and that baffles angled at 90 degrees to the wall were found in the prior art.  The panel added that the patent specification “is intended to support and inform the claims, and here it makes it unmistakably clear that the invention involves baffles angled at other than 90 [degrees].”  The dissenting judge argued that the panel had improperly limited the claims to the specific embodiment of the invention disclosed in the specification, rather than adopting the “plain meaning” of the term “baffles.”  The court of appeals agreed to rehear the appeal en banc.

Issue.

Should a term in a claim of a patented invention be restricted to corresponding structures disclosed in the specification, or their equivalents, when the plain meaning of the term can be used without causing the 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, when the plain meaning of the term can be used without causing the limitation.  The issue of the claim interpretation is framed by § 112 of the Patent Act (35 U.S.C. § 112).  The second paragraph of that section instructs the court to look to the language of the claims to determine what “the applicant regards as his invention.”  On the other hand, the first paragraph requires that the specification describe the invention presented in the claims.  Therefore, the main question presented is the extent to which the court should resort to and rely on a patent’s specification in seeking to establish the proper scope of its claims.  First, it is a “bedrock principle” of patent law that “the claims of a patent define the invention to which the patentee is entitled the right to exclude.”  Also, the words of a claim are given their ordinary and usual 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 believed to read the claim term in the context of the entire patent, including the specification, not just in the context of the particular claim where the disputed term appears.  When the ordinary meaning of claim language is obvious even to lay judges, general application dictionaries may be helpful.  However, if the ordinary meaning is not obvious, the court must look to the sources available to the public that show the meaning of the language in question that a person skilled in the art would have understood.  Those sources include the words of the claims themselves, the remainder of the specification, the prosecution history, and external evidence regarding relevant scientific principles, the meaning of technical terms, and the state of the art.  Claims must be read in view of their own specifications.  External evidence may include experts and technical dictionaries.  However, placing greater emphasis on technical dictionaries and encyclopedias in approaching the construction of claim language, rather than on the specification and prosecution history, conflicts with rulings that the specification is the single best guide to the meaning of a disputed term and that the specification acts as a dictionary when it specifically defines terms used in the claims or when it defines terms by implication.  The main problem with considering the dictionary as so important 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.  The “ordinary meaning” of a claim term when viewed properly is the meaning an ordinary artisan would determine after reading the entire patent.  The problem resulting from the district court starting every case using the broad dictionary definition of a word is a failure to fully understand how the specification totally limits that definition and the error will systematically cause the construction of the claim to be overly expansive.  If the court focuses from the beginning on how the patentee used the claim term in the claims, specification, and prosecution history, the risk of systematic over-breadth is greatly reduced, rather than starting with a broad definition and then cutting it down.  In cases that are 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 just to be correct in nature, trying 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 separating the claim language from the specification.  It is clear from Claim 1 when applying these principles 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 specify that “baffles” 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 written in the patent to be load-bearing objects with the purpose of checking, impeding, or obstructing flow.  Several times the specification discusses positioning the baffles so as to deflect projectiles.  It is clear in the patent that the invention envisions baffles that serve that function, but 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.  Several other purposes are served by the baffles as discussed in the specification, such as providing structural support.  Also, the specification provides for “overlapping and interlocking the baffles to produce substantially an intermediate barrier wall between the opposite [wall] faces” to create insulation compartments.  The fact that the written description of the ‘798 patent sets forth multiple objectives to be served by the baffles recited in the claims confirms that the term “baffles” should not be read restrictively to require that the baffles in each case must serve all recited functions.  In this case, although deflecting projectiles is an advantage of the baffles, it is not required by the patent that inward extending structures always be capable of performing that function.  Accordingly, the disclosure and claims of the ‘798 patent would not be interpreted by a person skilled in the art to mean that a structure extending inward from one of the wall faces is a “baffle” if it is at an acute or obtuse angle, but is not a “baffle” if it is disposed at a right angle.  Remanded.

Discussion.

This case has resulted in limited exclusive reliance on dictionaries as an “objective” and presumptive source for meanings of claim terms.  After Phillips, courts may still use dictionaries along with the specification, especially when no included evidence exists in the specification regarding a term’s specialized meaning, but the specification must be referenced to the extent possible.