The opinion of the court was delivered by: Judge James B. Zagel
MEMORANDUM OPINION AND ORDER
Plaintiffs One World Technologies, Ltd. and Ryobi Technologies, Inc. (collectively, "One World") allege infringement of United States Patent No. 6,658,976 (the "'976 Patent" or "the Patent") by Defendants Rexon Industrial Corporation, Ltd. and Power Tool Specialists, Inc. (collectively, "Rexon"). The invention claimed in the '976 Patent improves upon traditional miter saws by offering an ergonomic handle. The Patent is also directed to the design of a miter saw in which the handle adjusts relative to the rotation of the miter saw blade, allowing the operator to maintain a comfortable grip on the handle when the blade is tilted on an angle. The parties dispute the meaning of a number of terms found in the claims.
Claim construction is a matter of law for the court to decide. Markman v. Westview Instruments, Inc., 517 U.S. 370 (1996). In order "[t]o ascertain the meaning of claims, [the court] consider[s] three sources: The claims, the specification, and the prosecution history." Markman v. Westview Instruments, Inc., 52 F.3d 967, 979 (Fed. Cir. 1995), aff'd 517 U.S. 370 (1996). These three sources are the intrinsic evidence, public records available for all to consult when determining the meaning and scope of a patent claim. Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996). When the intrinsic evidence unambiguously describes the scope of a patented invention, reliance on extrinsic evidence, such as expert testimony and treatises, is inappropriate. Id. at 1583.
Claim interpretation begins with the actual words of the claims. Bell Communications Research v. Vitalink Communications Corp., 55 F.3d 615, 619-20 (Fed. Cir. 1995); see also Teleflex, Inc. v. Ficosa N. Am. Corp., 299 F.3d 1313, 1324 (Fed. Cir. 2002). Generally, the words, phrases and terms in patent claims should receive their ordinary and accustomed meaning. Johnson Worldwide Assocs. v. Zebco Corp., 175 F.3d 985, 989 (Fed. Cir. 1999). The strong presumption in favor of the ordinary meaning may be overcome only when the patentee "clearly set[s] forth a definition for a claim term in the specification." Anchor Wall Sys. v. Rockwood Retaining Walls, Inc., 340 F.3d 1298, 1306 (Fed. Cir. 2003) (citing Johnson Worldwide Assocs., 175 F.3d at 989-90); see also Dow Chem. Co. v. Sumitomo Chem. Co., 257 F.3d 1364, 1372 (Fed. Cir. 2001) ("a technical term used in a patent claim is interpreted as having the meaning a person of ordinary skill in the field of the invention would understand it to mean") (citation omitted). A patentee "may choose to be his own lexicographer and use terms in a manner other than their ordinary meaning, as long as the special definition of the term is clearly stated in the patent specification or file history." Vitronics Corp., 90 F.3d at 1582 (citation omitted).
Additionally, "[c]laims must be read in view of the specification, of which they are a part." Markman, 52 F.3d at 979 (citations omitted). The specification may reveal "whether the inventor has used any terms in a manner inconsistent with their ordinary meaning." Vitronics Corp., 90 F.3d at 1582. "The specification is always highly relevant to the claim construction analysis. Usually, it is dispositive; it is the single best guide to the meaning of a disputed term." Id. The specification also serves as an aid in determining "the meaning of the claim term as it is used . . . in the context of the entirety of [the] invention." Interactive Gift Express, Inc. v. Compuserve Inc., 256 F.3d 1323, 1332 (Fed. Cir. 2001) (quoting Comark Communs., Inc. v. Harris Corp., 156 F.3d 1182, 1187 (Fed. Cir. 1998)).
The claims, however, are not limited to the embodiment shown in the specifications. See Anchor Wall Sys., 340 F.3d at 1307; Transmatic, Inc. v. Gulton Indus., 53 F.3d 1270, 1277 (Fed. Cir. 1995). Limitations appearing only in the specifications cannot be read into a claim because "the claim, not the specification, measures the invention." Howes v. Zircon Corp., 992 F. Supp. 957, 961 (N.D. Ill. 1998) (citing SRI Int'l v. Matsushita Elec. Corp., 775 F.2d 1107 (Fed. Cir. 1985)). However, when the specification is "clear that the invention does not include a particular feature, that feature is deemed to be outside the reach of the claims of the patent, even though the language of the claims, read without reference to the specification, might be considered broad enough to encompass the feature in question." SciMed Life Sys., Inc. v. Advanced Cardiovascular Sys., Inc., 242 F.3d 1337, 1341 (Fed Cir. 2001).
Each patent has a corresponding publicly-available record called the prosecution history, which details the proceedings before the Patent and Trademark Office ("PTO"). The prosecution history may limit the interpretation of claim terms by revealing express representations made by the applicant regarding the scope of the claims or by excluding interpretations that were disclaimed during prosecution. Vitronics, 90 F.3d at 1582-83 (citations omitted). However, "unless altering claim language to escape an examiner rejection, a patent applicant only limits claims during prosecution by clearly disavowing claim coverage." Kopykake Enters. v. Lucks Co., 264 F.3d 1377, 1382 (Fed. Cir. 2001) (internal quotation and citation omitted). Any such disavowal "must be clear and unmistakable." Anchor Wall Sys., 340 F.3d at 1307.
The parties dispute several terms found in Claim 1 of the '976 Patent, which reads:
A miter saw comprising: a base; an arm assembly having a fixed end pivotally attached to the base, a free distal end forming a handle spaced outwardly therefrom and a central region therebetween provided with a rotary spindle supporting a cutting disc; said handle comprising a D-shaped portion, said D-shaped portion including a grip portion, said D-shaped portion being connected to said central region via a rotatable joint to permit rotation of said handle, said handle and said rotatable joint having a common pivot axis therethrough; said rotatable joint comprising a locking mechanism cooperating with the central region for permitting selective handle rotation about said pivot axis and for maintaining a selected orientation of said handle portion relative to said central region during a cutting operation of the miter saw. ('976 Patent, Col. 4, ll. 50-67; Col. 5, ll. 1-2.)
The first term in dispute is "a free distal end forming a handle spaced outwardly therefrom." One World asks me to construe the term as meaning "a handle formed at the other end of the arm assembly." Rexon does not dispute this choice of words, but argues that it is an incomplete definition, which ignores language about the spacing of the handle. Rexon's proposed construction defines the distal end in relation to the fixed end of the machine, i.e., as its opposite. This limitation is supported by language in the specification that is cited by both parties. ('976 Patent, Col. 4, ll. 3-4) ("a handle 66 at the opposite end of the arm assembly 62"). For this reason, I construe the disputed term as "a handle at the end of the arm assembly opposite the fixed end, and spaced away from the distal end."
The second term in dispute is "said handle comprising a D-shaped portion." The shape of the handle claimed by the inventor is at the heart of the parties' dispute. One World would construe this claim as "the handle includes a portion generally in the shape of a 'D,'" while Rexon would construe the claim as "a portion of the handle is formed in the shape of a capital letter 'D' which, by definition, is uniplanar." The parties agree that "D-shaped handle" has an ordinary meaning to persons skilled in the relevant art.*fn1 In fact, "D-type" handles or "D-handles" are a conventional structure for miter saw handles, well known to persons of ordinary skill in the art. In its review of prior art, the '976 Patent discusses three "common" handle shapes, including "a horizontal D-handle." (Id. at Col. 1, ll. 31-34.) The specification also discusses how the rotatable handle feature found in a preferred embodiment can be used in a "D-handle type miter saw handle." (Id. at Col. 4, ll. 31-35.)
One World does not cite to any part of the specification in support of its effort to broaden the ordinary meaning of D-shaped handles to handles "generally" in the shape of the letter "d." The inventor's use of the term "D-shaped" within the claim is consistent with references to the D-shaped handles common in the art that appear throughout the specification. The prosecution history also references conventional D-type handles commonly known in the art, and distinguishes these handles--on grounds other than shape--from the handle of the proposed invention. Nothing in the history suggests that the handles of the prior art or of the invention need be only generally in the shape of the letter "D".*fn2 In sum, the intrinsic evidence does not support One World's effort to expand the ordinary meaning of "D-shaped."
Rexon's proposed limitation of the term is more challenging: it asks me to find that the shape disclosed by the invention is uni-planar. Rexon argues that its proposed construction does not improperly narrow scope of the claim, but only elucidates the inherent meaning of the term "D-shaped." Pointing primarily to the drawings and descriptions found in the '976 specification and prior art, Rexon argues that these indicate only uniplanar handles. Rexon argues that "something shaped like a 'D' must be generally uni-planar so that it resembles and can be recognized as having the shape of the letter." Although both the drawings and the descriptions in the '976 Patent specification depict the D-shape of the handle from the perspective of a single plane, I find no evidence that this aspect of the specification was intended as a strict limitation on the claim, or that it is otherwise inherent in the definition of "D-shaped."*fn3 ...