Laitram Corp. v. Cambridge Wire Cloth Co.

• Decision Date: 12 December 1988
• Docket Number: 88-1210,Nos. 88-1209,s. 88-1209
• Citation: 9 USPQ2d 1289,863 F.2d 855
• Parties: , 9 U.S.P.Q.2d 1289 The LAITRAM CORPORATION and Intralox, Inc., Plaintiffs-Appellants, v. CAMBRIDGE WIRE CLOTH COMPANY, Defendant-Appellee.
• Court: U.S. Court of Appeals — Federal Circuit

Page 855

863 F.2d 855

57 USLW 2376, 9 U.S.P.Q.2d 1289

The LAITRAM CORPORATION and Intralox, Inc., Plaintiffs-Appellants, v. CAMBRIDGE WIRE CLOTH COMPANY, Defendant-Appellee.

Nos. 88-1209, 88-1210.

United States Court of Appeals Federal Circuit.

Dec. 12, 1988.

Rehearing Denied Jan. 25, 1989.

Suggestion for Rehearing In Banc Declined Feb. 9, 1989.

Paul J. Hayes, Weingarten, Schurgin, Gagnebin & Hayes, Boston, Mass., argued for plaintiffs-appellants. With him on the brief was Victor B. LeBovici.

G. Franklin Rothwell, Bernard, Rothwell & Brown, P.C., Washington, D.C., argued for defendant-appellee. With him on the brief was Bruce J. Hendricks.

Before MARKEY and RE ^*, Chief Judges, and NICHOLS, Senior Judge.

MARKEY, Chief Judge.

The Laitram Corporation and Intralox, Inc. (Laitram) appeal from a judgment of the United States District Court for the District of Maryland, No. S 83-3126, finding that the Cambridge Wire Cloth Company (CWC) did not infringe Patent Nos. 3,870,141, 4,051,949, and Re.30,341. We reverse and remand.

Background

In 1983, Laitram sued CWC for infringement of U.S. Patents 3,870,141 ('141), 4,051,949 ('949), 4,159,763 ('763) and Re.30,341 ('341). The accused products were CWC's modular plastic conveyor belt (CAM-CLEAN I) and a belt drive system. In 1985, the U.S. District Court for the District of Maryland upheld the validity of the patents, found each infringed, and enjoined further infringement. Laitram Corp. v. Cambridge Wire Cloth Co., 226 USPQ 289 (D.Md.1985), aff'd in part, rev'd in part, 785 F.2d 292, 228 USPQ 935 (Fed.Cir.), cert. denied, 479 U.S. 820, 107 S.Ct. 85, 93 L.Ed.2d 39 (1986) (the first trial). In a thorough and comprehensive opinion, the court outlined CWC's failed effort to obtain rights to the patented invention through merger, acquisition, or joint venture, followed by CWC's engagement of a design firm to "incorporate features similar to Laitram patents." Id. at 291. The court correctly interpreted the claims and fully described the inventions and patents in that opinion.

In mid-1986, CWC filed and the court denied a motion to exclude from the injunction a "redesigned" module (CAM-CLEAN II). In November 1986, CWC sought a judgment declaring CAM-CLEAN II non-infringing. The court dismissed that suit. When CWC began manufacture of CAM-CLEAN II, Laitram sued for infringement of claim 1 of the '141 patent, claim 21 of the '949 patent, and claim 1 of the '341 patent. Broadly, the '141 patent discloses plastic modules having links joinable by plastic rods to create a conveyor belt; the '949 patent discloses a module with raised ribs; and the '341 patent discloses a sprocket drive system for conveyor belts.

Laitram moved for a preliminary injunction and for a finding of contempt. The court consolidated all matters before it and conducted a six-hour trial on November 12, 1987. ¹ In an opinion dictated from the bench, the court found that CAM-CLEAN II infringed none of the three asserted claims and denied the contempt motion.

Issues

1. Whether the district court erred in determining noninfringement of the asserted claims of the '141, '949, and '341 patents.

2. Whether the district court properly denied the contempt motion.

OPINION

Introduction

This appeal again illustrates one of the many difficult dichotomies that lurk in the lacunae of patent law. On one side rests the very important, statutorily-created necessity of employing the clearest possible wording in preparing the specification and claims of a patent, one of "the most difficult legal instruments to draw with accuracy." ² On the other lies the equally important, judicially-created necessity of determining infringement without the risk of injustice that may result from a blindered focus on words alone. The former, set out in 35 U.S.C. Sec. 112, recognizes a competitor's need for precise wording as an aid in avoiding infringement. The latter is called the "doctrine of equivalents". While requiring a look at all the words while resisting their tyranny, ³ and requiring, because the claims measure the invention, a look at all claim limitations, the doctrine, in a proper case, "temper[s] unsparing logic and prevent[s] an infringer from stealing the benefits of an invention." Graver Tank & Mfg. Co. v. Linde Air Prods. Co., 339 U.S. 605, 608, 70 S.Ct. 854, 856, 94 L.Ed. 1097, 85 USPQ 328 at 330 (1950) (quoting Royal Typewriter Co. v. Remington Rand, 168 F.2d 691, 692, (2d Cir.1948) (L. Hand, J.)). In that sense, the doctrine recognizes a fact of the real business world: words are not misappropriated; claimed inventions are. ⁴

In the present case, the semantic antics of counsel at trial and in their briefs on appeal have obfuscated the true nature of the dispute as it must be perceived in law. ⁵ That obfuscation led in turn to a failure to apply the "substantially the same function in substantially the same way to obtain substantially the same result" guidance of Graver Tank, 339 U.S. at 608, 70 S.Ct. at 856, 85 USPQ at 330. ⁶

The basic facts are either undisputed or accepted here as found by the district court. The difficulty with the appealed judgment lies in the district court's application to the facts of the law governing determinations of infringement.

1. Infringement

The '141 Patent

(a) Claim Interpretation

Claim 1 of the '141 patent reads:

1. A module for constructing linked structures, said module comprising in combination:

a first plurality of link ends of substantially identical width, each being formed to circumscribe a pivotal hole, said hole of said first plurality being arranged coaxially;

a second like plurality of link ends of substantially identical width, each being formed to circumscribe a pivotal hole, said holes of said second plurality being arranged coaxially, the axes of respective holes of both pluralities of link ends being substantially parallel; and

a plurality of spaced apart elongated members each integrally formed with and joining a pair of corresponding link ends of said first and second pluralities, said members being joined by at least one cross rib also formed integrally therewith and extending parallel to said axes;

said link ends being dimensioned and spaced apart by a distance slightly greater than said width so that said module is end-to-end reversible, so that a plurality of said modules may be engaged with each other at said ends.

It is undisputed that all limitations of the claim, save the last, read directly on CAM-CLEAN II. The district court focused on the words "slightly greater", correctly viewing that adjectival phrase as a "sloppy term" requiring for its interpretation reference to the specification, the prosecution, and the prior litigation:

You cannot make exactly that determination [whether "slightly greater means .2 but not .3, or .3 but not .06."]. It is not exact. It is not scientific. It is a sloppy term, but slightly greater, even though it is a sloppy term, has no meaning for this case outside of the claims of Patent 141, as interpreted by the prosecution of that patent in the patent office and as interpreted by the prior history of this litigation, including Mr. Lapeyre's testimony, which is what he won on in the first suit.

Having had a witness measure the link end widths and the spacing between link ends of Laitram's commercial product and of the accused CAM-CLEAN II module, the court found the spacing in the former was 106% of the width and that in the latter was 135%. ⁷ Deeming the latter "more than slightly greater", the court found noninfringement. ⁸ As discussed below, application of the law governing infringement by equivalents renders that ultimate finding of noninfringement clearly erroneous.

The phrase "slightly greater" is not presented in a vacuum. The claim contains definitional parameters: "so that said module is end-to-end reversible, so that a plurality of said modules may be engaged with each other at said ends". ⁹ In addition, the district court properly interpreted the claim in light of the prosecution history in the first trial, defining "slightly greater" spacing in terms of its purpose, i.e., spacing that would "minimize bending and maximize shear".

Assuming, arguendo, the district court's interpretation of the phrase "slightly greater", in the second trial, as the 106% width in Laitram's product, CWC's 135% width may be seen as avoiding a finding of literal infringement. The question would remain, however, of whether CWC's 135% width constituted a change sufficient to escape a finding of infringement under the doctrine of equivalents.

(b) Doctrine of Equivalents

In the first trial, the court found that CAM-CLEAN I constituted an "infringement by equivalents of claim 1." 226 USPQ at 298. In this trial, the court's entire discussion of equivalence with respect to CAM-CLEAN II, reads:

It is true that all that has been done in the redesign of Cam-Clean II is an alteration of the spacing, relative spacing of the link ends.

That is true, but if the result is that when the patent language, the claim language is viewed in context of its prosecution history, as it has to be under the doctrine of equivalence (sic, equivalents), if the result is that even applying the doctrine of equivalence [sic] there is no longer a spacing between links that is only slightly greater than the width of the links, then there is no infringement. That is all there is to it. It is that simple.

To me the telling proof is made up in two ways. Number one, the tests, in my opinion--although the difference is admittedly small at working loads, at the higher loads, where you would test to ascertain the true strength of the material--in my judgment the tests show that the Cam-Clean II is less resistant to the bending and elongation forces than the original Cam-Clean, but that is not real [sic] really the most important question.

The most important question is, what is the spacing of the redesign Cam-Clean relative to the width of the link ends?

The...