dissenting-in-part.
I respectfully dissent from the court’s decision to affirm the district court’s judgment with respect to infringement by lines 1 and 2.
I do not agree that the claim limitation “crystallizing the granulate ... at a temperature of 220° C to 260° C” refers to the temperature of the heating medium. The claim is clear on its face, when read in light of the specification, that it refers to' the temperature of the granulate. Thus, the court erred in its instruction to the jury concerning the meaning of the claim and in permitting the jury to rely on such extrinsic testimony as that given by Dr. Phillips.
When the granulate is crystallized “at a temperature,” the granulate is at that temperature. I do not believe the specification is unclear on this point. Nothing in the patent, the prosecution history, or even the trial testimony indicates otherwise. The majority opinion, with great care, provides much analysis on this issue, but it is incorrect. Each of *1562the bases for its conclusion that heating medium temperature is intended is a speculative guess; the opinion repeatedly uses the words “suggests” and “apparently,” whereas the references in the specification to the temperature of the material being acted upon are clear references to that material.
The summary of the invention indicates, 112 patent, column 2, lines 30-32, that the granulate is crystallized at temperatures of 220°C to 260°C. It then states that the crystallized granulate is then transferred at the same temperature to a reactor where it is polycondensed at a temperature equivalent to, or lower than, the crystallization temperature. It also states, at column 2, lines 56-58, that, according to a preferred embodiment, the crystallization is effected at a temperature of 230°C to 245°C. The specification also, at column 4, lines 33-35, makes a statement that the examples are “run at [particular] temperatures,” indicating that the materials being treated are “at” that temperature. It is clear from the specification, consistent with conventional chemical terminology, that the temperature of the granulate is what is meant in each ease.
The examples are similarly clear. At column 3, lines 46-47, the text of examples 1-18 states: “The granulate was heated in the continuously operating mixer to the temperature values, Tk, as indicated in Table 1____” When the granulate is heated to a temperature, it, not the heating medium, gets to that temperature. Examples 19-26, at column 5, line 14, refer to “temperature measurements.” One obviously “measures” the temperature of the reactant rather, than “setting” the temperature of a heating medium. Equally telling.is this use of a symbol for the temperature of the substance undergoing crystallization, Tk, which the record shows conventionally means the temperature of the substance being crystallized. (Eastman’s expert witnesses, Drs. Phillips and Gintis, as well as Goodyear’s expert witness, Dr. Harris, each indicated that he and other polymer chemists generally use this symbol and the synonymous phrase “crystallization temperature” to refer to the temperature of the material undergoing the reaction.) See Markman v. Westview Instruments, Inc., 52 F.3d 967, 980, 34 USPQ2d 1321, 1330 (Fed.Cir.1995) (in banc), aff'd, — U.S.-, 116 S.Ct. 1384, 134 L.Ed.2d 577, 38 USPQ2d 1461 (1996) (“[A] patentee is free to be his own lexicographer. The caveat is that any special definition given to a word must be clearly defined in the specification.”) (citations omitted). At column 7, lines 22-23, examples 45-50, the specification states: “The crystallization temperature was 245°C. The solid state polycondensation temperature was 240°C.” Nothing could be clearer; during crystallization and polycondensation the granulate was at those temperatures.
Nowhere in the description of the process in the specification is there reference to setting the temperature of a heating medium. The words “heating medium,” constantly referred to in the majority opinion as the referent of the phrase “at a temperature” in the claims, do not appear in the portion of the specification describing the claimed process. They only appear in the portion describing apparatus to measure granulate stickiness, see column 7, lines 52-53, which is not the invention and which it is a purpose of the invention to prevent, see column 2, lines 39-41. Even in this section, at column 8, lines, 31-32, the specification describes a temperature feeler which measures the granulate temperature to correlate it with granulate stickiness. This is distinctly different from the description of the process provided earlier in the specification, and the claims track the description of the process. I will not prolong this opinion by citing further places in the specification indicating that temperature references refer to the material being acted upon, not to the temperature of the heating medium.* Clearly the temperature is that of the granulate, not the heating medium.
The trial court and, regrettably, the majority of this panel, have simply been misled concerning what the specification clearly states and means. The analyses in the majority opinion leading to the contrary conclu*1563sion are not in my view convincing, even to show an ambiguity. The interesting analyses of sentence structure and the meaning of the words “at,” “to,” “under,” “utilizing,” and “used” prove nothing. They do not indicate that the temperature is not of the granulate. Likewise, granulate temperature is fully consistent with the five-degree increments in Table 1.
Given the clear meaning of “at a temperature,” I believe that there is no need to resort to extrinsic evidence to resolve an ambiguity in the claim. The majority opinion acknowledges that extrinsic evidence cannot be admitted to contradict the claims, the specification, and the prosecution history. See Markman v. Westview Instruments, Inc., — U.S. -, -, 116 S.Ct. 1384, 1395, 134 L.Ed.2d 577, 38 USPQ2d 1461, 1470 (1996) (“[A]ny credibility determinations will be subsumed within the necessarily sophisticated analysis of the whole document, required by the standard construction rule that a term can be defined only in a way that comports with the instrument as a whole.”); Trilogy Communications, Inc. v. Times Fiber Communications, Inc., 109 F.3d 739, 744, 42 USPQ2d 1129, 1133 (Fed.Cir.1997) (“[Ejxtrinsic evidence may be relied on-when needed to interpret claims, but only when it does not contradict the intrinsic record consisting of the claims themselves, the specification, and the prosecution history.”); Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1584, 39 USPQ2d 1573, 1578 (Fed.Cir. 1996) (“[Ejxtrinsic evidence in general, and expert testimony in particular, may be used only to help the court come to a proper understanding of the claims; it may not vary or contradict the claim language. Nor may it contradict the import of other parts of the specification.”) (citation omitted). While correctly quoting the rule, the majority misapplies it. It has ratified the trial court’s use of extrinsic testimony to contradict the specification. '
However, even if extrinsic evidence such as Phillips’s testimony is considered, it is ambiguous at best. Notwithstanding his admission of the common meaning of the phrase “crystallization temperature,” Phillips stated that in the more specialized field of industrial chemical production someone of “ordinary skill in that art” would read that phrase as a “setting” for the heating medium. That contradicts the specification. One must read and rely on the specification, not invent categories of activity to which witnesses can assign different meanings for the same language. The patent teaches others of skill in the art how to make the claimed polymer, consistently using language meaningful to chemists; the claims track this language. It does not tell how to implement the fine points of industrial-scale techniques. It speaks to those who read the specification and carry out the claimed process, not to plant technicians.
Although proper interpretation of the claims as above is sufficient to result in a judgment for Goodyear, the majority opinion’s interpretation of the meaning of the claim phrase “continuously polycondensing ... at a temperature equivalent to, or lower than, the crystallization temperature” is also wrong. As the majority opinion states, quoting from the Supreme Court’s Markman opinion, — U.S. at-, 116 S.Ct. at 1395, 134 L.Ed.2d 577, 38 USPQ2d at 1470, this interpretation is based upon “the trial court’s ‘trained ability to evaluate [expert] testimony ... and ... “better position to ascertain whether an expert’s proposed definition fully comports with the specification and claims.’ ” This language, while directed to the differences between judge and jury in Markman, is inapplicable here because the trial court’s “trained ability” and “better position” to evaluate witnesses are irrelevant when reading the specification is what counts. The appellate court is equally well situated to read the specification. The majority opinion’s claim interpretation is also based upon a reexamination examiner’s distinction between an initial crystallization temperature and further crystallization in relation to prior art. This is irrelevant to the present infringement question because Goodyear’s polycondensation occurred at a temperature greater than either crystallization step; therefore Goodyear could not infringe the claims, which require that polycondensation occur at an equivalent or lower temperature.
Given the proper claim construction, the trial court should have granted judgment as a matter of law that lines 1 and 2 do not infringe the ’112 patent.
*1564ORDER
July 2, 1997.
A combined petition for rehearing and suggestion for rehearing in banc having been filed by the Appellant, and the petition for rehearing having been referred to the panel that heard the appeal, and thereafter the suggestion for rehearing in banc having been referred to the circuit judges who are in regular active service, it is ORDERED
that the petition is GRANTED for the limited purpose of making additions to the opinion.
[Editor’s Note: Amendments incorporated for purpose of publication.]
It is further ORDERED that the suggestion for rehearing in banc is DECLINED.
The mandate of the court will issue on July 9,1997.
Not surprisingly, the prosecution history in reexamination also contains multiple references to the temperature of the granulate, including, e.g., the passages: "the PET granules 'provide as much as a 10°C increase in their temperature "the plastics material has been preheated to a temperature in the range and, "the granular material was preheated to 220°C____"