Morton Intern., Inc. v. Cardinal Chemical Co.

• Decision Date: 20 March 1992
• Docket Number: 91-1175,Nos. 91-1174,s. 91-1174
• Citation: 22 USPQ2d 1231,959 F.2d 948
• Parties: , 23 U.S.P.Q.2d 1362 MORTON INTERNATIONAL, INC., Plaintiff-Appellant, v. CARDINAL CHEMICAL COMPANY, a partnership, W.M. Quattlebaum, Jr., Dorothy Quattlebaum, and W.M. Quattlebaum, III, individuals, Cardinal Manufacturing Co., and Cardinal Stabilizers, Inc., Defendants/Cross-Appellants.
• Court: U.S. Court of Appeals — Federal Circuit

Page 948

959 F.2d 948

22 U.S.P.Q.2d 1231, 23 U.S.P.Q.2d 1362

MORTON INTERNATIONAL, INC., Plaintiff-Appellant, v. CARDINAL CHEMICAL COMPANY, a partnership, W.M. Quattlebaum Jr., Dorothy Quattlebaum, and W.M. Quattlebaum, III individuals, Cardinal Manufacturing Co., and Cardinal Stabilizers, Inc., Defendants/Cross-Appellants.

Nos. 91-1174, 91-1175.

United States Court of Appeals Federal Circuit.

March 20, 1992.

Rehearing Denied April 17, 1992.

Suggestion for Rehearing

In Banc Declined May 7, 1992.

Gordon R. Coons, Leydig, Voit & Mayer, Chicago, Ill., argued, for plaintiff-appellant. With him on the brief were John E. Resenquist and Jeffrey S. Ward. Also on the brief was Gerald K. White, Morton International, Inc., Chicago, Ill.

Charles F. Schill, Adduci, Mastriani, Meeks & Schill, Washington, D.C., argued for defendants/cross-appellants. With him on the brief were William O. Sweeny, III, Arthur L. Coleman, Nelson Mullins and Elizabeth R.P. Bowen, Riley & Scarborough, Columbia, S.C.

Jerome G. Lee, Arlington, Va., was on the brief for amicus curiae, American Intellectual Property Law Ass'n. With him on the brief were William C. Rooklidge and Joseph R. Re, Knobbe, Martens, Olson & Bear, Newport Beach, Cal. Also on the brief were Walter N. Kirn and William L. LaFuze, of counsel.

Brian G. Brunsvold, Finnegan, Henderson, Farabow, Garrett & Dunner, Washington, D.C., was on the brief for amicus curiae, Atochem North America, Inc. With him on the brief were Herbert H. Mintz, Richard B. Racine and Michael D. Kaminski. Also on the brief was Stanley A. Marcus, Deputy Gen. Counsel--Patents, Atochem North America, Inc., Philadelphia, Pa., of counsel.

Before MAYER, LOURIE, and CLEVENGER, Circuit Judges.

PER CURIAM.

This appeal and cross-appeal are from the December 14, 1990, judgment of the United States District Court for the District of South Carolina, 6:83-889-OK. The patentee, Morton International, Inc., contends that the district court erred in finding its U.S. Patents 4,062,881 ('881) and 4,120,845 ('845) not infringed by Cardinal Chemical Company, et al.; and in concluding that both patents are invalid. Cardinal contends that the district court erred in failing to award attorney fees for an exceptional case under 35 U.S.C. § 285, and that this court should sanction Morton's appeal as frivolous. We affirm the court's judgment in all respects, except we vacate that part of the judgment holding the '881 and '845 patents invalid. We also reject Cardinal's assertion that this appeal is frivolous.

BACKGROUND

The patents in suit are directed to a family of compounds which are used as additives or heat stabilizers for polyvinyl chloride (PVC). The heat stabilizers protect the PVC from decomposition, discoloration, and loss of strength. The particular heat stabilizers disclosed in the '881 and '845 patents are directed to organotin compounds, in particular to organotin mercaptoalkyl carboxylic acid ester sulfides. Only Claim 1 of each patent is at issue. ¹ The key limitations of the claims are (1) the bonding of the organotin compound, referred to by the parties as "partial connectivity," wherein a tin atom is bonded to a sulfur atom, the sulfur atom is bonded to a second tin atom, and the second tin atom is bonded to a mercaptoalkyl ester (referred to by the parties as a "reverse ester"); and (2) "the organotin compound [has] an amount of tin within the range from 10 to 42% by weight and an amount of sulfur within the range from 8 to 42% by weight."

The '881 and '845 patents have had considerable exposure to the courts, as Morton has filed infringement actions in three separate district courts against different defendants. In the first, Morton filed suit against Argus Chemical Corporation in the United States District Court for the Eastern District of Louisiana. After trial, the district court entered judgment, holding the patents invalid and not infringed. Morton Thiokol, Inc. v. Witco Chemical Corp., et al. No. 84-5685 (E.D.La., filed November 28, 1984).

On appeal, we affirmed the district court's judgment of non-infringement and vacated the invalidity judgment, ruling that the affirmance made it unnecessary to review the issue of invalidity. Morton Thiokol, Inc. v. Argus Chemical Corp., 873 F.2d 1451, 11 USPQ2d 1152 (Fed.Cir.1989) (non-precedential).

In the second action, the appeal of which is now before this court, Morton again filed suit, this time against Cardinal, alleging that Cardinal sold mixtures containing the claimed compounds. After trial, the district court made lengthy findings and conclusions and held that the claims were invalid under 35 U.S.C. § 112 because the specification was not enabling and the claims were indefinite. It further held that Cardinal's heat stabilizer products did not infringe those claims, either literally or under the doctrine of equivalents. Morton and Cardinal now appeal and cross-appeal this judgment, requiring us to review once more the infringement and/or validity of the '881 and '845 patents. ²

DISCUSSION

I.

A finding of literal infringement requires that the asserted claims, as properly construed, read on the accused product. Envirotech Corp. v. Al George, Inc., 730 F.2d 753, 758, 221 USPQ 473, 477 (Fed.Cir.1984). The patentee has the burden of proving infringement by a preponderance of the evidence. SmithKline Diagnostics, Inc. v. Helena Laboratories Corp., 859 F.2d 878, 889, 8 USPQ2d 1468, 1477 (Fed.Cir.1988). The first step in determining infringement is thus to construe the claims. Fonar Corp. v. Johnson & Johnson, 821 F.2d 627, 631, 3 USPQ2d 1109, 1112 (Fed.Cir.1987), cert. denied, 484 U.S. 1027, 108 S.Ct. 751, 98 L.Ed.2d 764 (1988). The second step is to decide whether each limitation in the properly construed claims is found, either literally or equivalently, in the allegedly infringing compounds. Id. Although claim interpretation is a question of law, subject to de novo review on appeal, the district court's ultimate finding on infringement, as well as subordinate findings relating to proper claim construction, are issues of fact, reviewed under a clearly erroneous standard. See H.H. Robertson Co. v. United Steel Deck, Inc., 820 F.2d 384, 389, 2 USPQ2d 1926, 1929 (Fed.Cir.1987) (interpretation of a claim may depend on evidentiary material about which there is a factual dispute); Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261, 1269-70, 229 USPQ 805, 811 (Fed.Cir.1986) (determination of infringement is a question of fact), cert. denied, 479 U.S. 1030, 107 S.Ct. 875, 93 L.Ed.2d 829 (1987).

Morton argues that the district court erred in interpreting Claim 1 and that the court's misinterpretation resulted in errors in the court's conclusions as to both infringement and invalidity. More particularly, Morton claims that the district court misconstrued the claims by restricting the type of evidence Morton could use to show the existence of the claimed compound in Cardinal's mixture to: (1) isolation and (2) nuclear magnetic resonance (NMR) data showing simultaneous tin-tin coupling and Carbon-13 splitting as the only method to prove the partial connectivity of Claim 1. We disagree.

On review of the record, it is clear that the district court did not construe Claim 1 to require isolation. The court merely required Morton to identify the claimed compounds in Cardinal's mixtures to confirm their existence. The court specifically found that "[n]o amount of testing by equipment or methods available [ ] can identify, isolate or separate any compound claimed by the '881 or '845 patents." Morton's reliance on In re Breslow, 616 F.2d 516, 205 USPQ 221 (CCPA 1980), to show error in the district court's finding is misplaced.

In Breslow, the compound in question could not be isolated, but was conceded to exist. The court expressly recognized that the existence of the compound was not in question. Id. at 518, 205 USPQ at 224. In the present case, however, the existence of the claimed partial connectivity in the Cardinal mixture is the essence of the dispute, and its existence has never been established. The court specifically acknowledged that under Breslow, "it is not imperative that the compounds be isolated in order to be claimed." The court, in determining whether the claims were infringed, used isolation as simply a possible means of such proof.

At trial, one of the ways Morton suggested one could analytically prove the existence of the claimed partial connectivity in Cardinal's mixtures was high-resolution Tin-119 NMR. However, the court observed the conflicting testimony of Morton's expert, Dr. Mesch, and Cardinal's NMR expert, Dr. Ellis, and found Dr. Ellis's more credible. The court found Dr. Mesch's identification of "at least eight peaks in a spectrum of the Cardinal product as possibly having the claimed [partial connectivity]" discredited by Dr. Ellis's conclusions that some of Mesch's identified peaks did not indicate the partial connectivity, but were caused by other elements present in the sample. The court determined that:

even after Morton and Cardinal have each expended extraordinary sums of money on state of the art testing, these organotin components of the accused Cardinal products cannot be identified as containing the claimed connectivity as specified in the '881 and '845 patents.

It further determined that there is "no objective support for the actual existence of the claimed connectivities." Therefore, the court had no reason to determine whether Cardinal's product contained the specified weight percentages of tin and sulfur claimed in the patents at issue.

Morton also argues that its building block theory shows the existence of the claimed partial connectivity, and that the district court failed to consider it. This theory is essentially that the Cardinal stabilizers contain four moieties-butyltin, sulfide, mercaptoethyltallate, and mercaptoethanol--and that these structures or "building blocks" can combine to form particular...