Hoganas AB v. Dresser Industries, Inc.

• Decision Date: 10 November 1993
• Docket Number: No. 92-1526,92-1526
• Citation: 28 USPQ2d 1936,9 F.3d 948
• Parties: HOGANAS AB, Plaintiff-Appellant, v. DRESSER INDUSTRIES, INC., Defendant-Appellee.
• Court: U.S. Court of Appeals — Federal Circuit

Page 948

9 F.3d 948

28 U.S.P.Q.2d 1936

HOGANAS AB, Plaintiff-Appellant, v. DRESSER INDUSTRIES, INC., Defendant-Appellee.

No. 92-1526.

United States Court of Appeals Federal Circuit.

Nov. 10, 1993.

Rehearing Denied; Suggestion for Rehearing In Banc Declined

Jan. 7, 1994.

Richard Linn, Marks & Murase, Washington, DC, argued for plaintiff-appellant. Of counsel was Peter A. Dankin.

Roy W. Hardin, Richards, Medlock & Andrews, Dallas, TX, argued for defendant-appellee. With him on the brief was V. Bryan Medlock, Jr. Thomas R. Felger, Baker & Botts, L.L.P., Dallas, TX, represented defendant-appellee.

Before PLAGER, Circuit Judge, SMITH, Senior Circuit Judge, and CLEVENGER, Circuit Judge.

PLAGER, Circuit Judge.

This is a patent infringement case which comes to us by way of appellant Hoganas AB's (Hoganas) appeal of the decision of the District Court for the Western District of Pennsylvania, Civil Action No. 89-304, granting appellee Dresser Industries, Inc.'s (Dresser) motion for summary judgment of non-infringement of U.S. Patent No. 3,982,953 (the '953 patent), both literally and under the doctrine of equivalents. We affirm.

I. BACKGROUND

Hoganas is the owner of the '953 patent. ¹ That patent is directed to a particular composition of materials used to form monolithic refractory linings for industrial furnaces. ² The composition is configured to minimize the time required for drying when such a lining is first applied to the furnace in a wet and pasty state. Attempts had been made to speed up the drying process, and thus minimize the required down-time, through the application of heat. However, these attempts were not entirely successful because, with the available compositions, there was no means of relieving the pressure that built up as the water evaporated into steam. The result was that the lining might explode during the drying process.

With the claimed composition, this problem is solved through the addition of "straw-shaped, channel-forming elements." These elements function to form channels which release the steam that builds up as heat is applied in the drying process. Accordingly, they prevent the explosions that occurred with prior compositions and thus allow the drying process to progress more quickly.

That patent contains 7 claims, of which claim 1 is the broadest:

1. In a refractory mass of the type used for casting, ramming or stamping refractory linings and for metallurgical ladles or tapping channels and composed of 60 to 95% by weight of refractory grog and 40 to 5% by weight of binder, the improvement which comprises said mass further containing 0.05 to 0.35% by weight, based on the solids content of the mass without any additive, of straw-shaped, channel-forming elements equally distributed throughout the mass, whereby rapid drying of the mass is made possible.

On June 6, 1988, Hoganas filed suit against Dresser in the District Court for the Central District of California (where Dresser apparently had an established place of business), alleging that a refractory composition manufactured by Dresser (bearing the "Adtech" trade name), infringed the '953 patent. That action was subsequently transferred to the District Court for the Western District of Pennsylvania, the location of the specific Dresser division which manufactured the Adtech product.

On April 30, 1989, Dresser filed a motion for summary judgment of non-infringement. In support of that motion, Dresser submitted relevant excerpts of the '953 prosecution history, the affidavit of Thomas R. Kleeb, one of its employees, and an excerpt from the deposition of James F. Benzel, apparently Hoganas' expert. In opposition to that motion, Hoganas submitted Mr. Benzel's affidavit.

On December 17, 1991, the court appointed, with the consent of the parties, a special master to decide the motion. On March 20, 1992, the special master issued a report recommending that the motion be granted. The special master focused on the "straw-shaped, channel-forming elements" limitation. He concluded it was not literally met by the corresponding element in the Adtech product, vinyl chloride acetate fibers, because these fibers "are so fine as to be barely visible by the unaided eye," and thus "bear no resemblance to straw." He also concluded this limitation was not met under the doctrine of equivalents because Hoganas, through prosecution history estoppel, had relinquished coverage of compositions employing "capillary-size" fibers, including the acetate fibers in the accused product. ³

On April 19, 1992, the district court adopted the special master's report as the opinion of the court ⁴, and entered judgment of non-infringement. This appeal followed.

II. DISCUSSION

A.

On appeal of a grant of summary judgment, we independently review the record to determine whether any errors of law were made or whether there are any material issues of disputed fact that remain. E.g., London v. Carson Pirie Scott & Co., 946 F.2d 1534, 1537, 20 U.S.P.Q.2d 1456, 1458 (Fed.Cir.1991). If neither is the case, we must affirm.

B.

Hoganas argues that the district court erred in its literal infringement analysis. According to Hoganas, the court erroneously interpreted the "straw-shaped, channel-forming elements" limitation to mean "straw-sized." ⁵ This was error, argues Hoganas, because that limitation, when properly interpreted, does not impose any requirement as to size.

We agree. It is improper for a court to add "extraneous" limitations to a claim, that is, limitations added "wholly apart from any need to interpret what the patentee meant by particular words or phrases in the claim." E.I. Du Pont de Nemours & Co. v. Phillips Petroleum Co., 849 F.2d 1430, 1433, 7 U.S.P.Q.2d 1129, 1131 (Fed.Cir.), cert. denied, 488 U.S. 986, 109 S.Ct. 542, 102 L.Ed.2d 572 (1988). That appears to be what the district court did, however, by emphasizing the smallness of the fibers. The phrase "straw-shaped" unambiguously relates to shape not size. Thus, it was improper for the court to use that phrase as the vehicle for incorporating a size limitation into the claim. ⁶

Nevertheless, we have concluded that any error committed by the district court in this regard is harmless. Based on our independent review of the record, we have concluded the "straw-shaped" limitation imposes the requirement that the channel-forming elements be hollow. ⁷ Because the acetate fibers in the Adtech product are solid, that product does not literally infringe any claim of the '953 patent.

Our interpretation is fully supported by the ordinary meaning of the term "straw." ⁸ Although a patentee can be his own lexicographer, as we have repeatedly said, the words of a claim "will be given their ordinary meaning, unless it appears that the inventor used them differently." ZMI Corp. v. Cardiac Resuscitator Corp., 844 F.2d 1576, 1579, 6 U.S.P.Q.2d 1557, 1560 (Fed.Cir.1988) (citing Envirotech Corp. v. Al George, Inc., 730 F.2d 753, 759, 221 U.S.P.Q. 473, 477 (Fed.Cir.1984)). Based on our review of the '953 specification and prosecution history, we are not convinced the '953 inventors used this term differently from its ordinary meaning. For example, the specification provides several examples of channel-forming elements, viz., "straw or stalks of common cereals, grass, reed or similar natural materials," ⁹ or "[s]traw-shaped synthetic elements, e.g., made from paper, plastic or other organic materials," ¹⁰ such as "cut pieces of plastics [sic] sipper straw." ¹¹ None of these examples are identified as being solid, and most if not all, are unquestionably hollow. ¹² Although the documentation does not expressly identify the hollowness characteristic as contributing to the inventive concept, it is not inconsistent with that concept either. Moreover, a significant and possibly critical contribution for this feature can be readily inferred: it permits the release of steam before the elements are burned away, and, by reducing the amount of ash which is formed as the elements burn out, it reduces the risk that the channels will become clogged.

For all the foregoing reasons, we conclude one of skill in the art, the vantage point from which the proper interpretation of the claim is ultimately determined ¹³, would not have been put on notice that the term meant other than what it says. Such a one would be perfectly justified in giving the term its ordinary meaning. If Hoganas, who was responsible for drafting and prosecuting the patent, intended something different, it could have prevented this result through clearer drafting. For example, as discussed at the hearing, the phrases "cylindrically-shaped" or "rod-shaped" could have been used. It would not be appropriate for us now to interpret the claim differently just to cure a drafting error made by Hoganas. That would unduly interfere with the function of claims in putting competitors on notice of the scope of the claimed invention.

Hoganas argues that this interpretation is not supportable because the phrase "straw-shaped" refers to the general "elongated and thin" silhouette of the elements, and thus includes hollow and solid elements. We disagree. According to a dictionary definition provided by Hoganas, the term "shape" means the "external surface" of an object. Since the hollowness of straw is part of its external surface (in the sense it is exposed to the external environment and thus visible to an observer), that characteristic is part of its shape and thus included within the phrase "straw-shaped." ¹⁴ Thus, Hoganas' interpretation is the one that is insupportable.

Accordingly, we affirm the district court on the literal infringement issue.

C.

Hoganas next argues that the district court erred in its analysis of the doctrine of equivalents issue. According to Hoganas, the court erred in concluding that Hoganas, through prosecution history estoppel, had relinquished coverage of capillary-sized fibers.

The essence of prosecution history estoppel is that a patentee...