Ecolochem, Inc. v. Southern California Edison Co.

• Decision Date: 05 June 1996
• Citation: 91 F.3d 169
• Parties: NOTICE: Federal Circuit Local Rule 47.6(b) states that opinions and orders which are designated as not citable as precedent shall not be employed or cited as precedent. This does not preclude assertion of issues of claim preclusion, issue preclusion, judicial estoppel, law of the case or the like based on a decision of the Court rendered in a nonprecedential opinion or order. ECOLOCHEM, INC., Plaintiff-Appellant, v. SOUTHERN CALIFORNIA EDISON COMPANY, Defendant-Appellee.
• Court: U.S. Court of Appeals — Federal Circuit

Page 169

91 F.3d 169

NOTICE: Federal Circuit Local Rule 47.6(b) states that opinions and orders which are designated as not citable as precedent shall not be employed or cited as precedent. This does not preclude assertion of issues of claim preclusion, issue preclusion, judicial estoppel, law of the case or the like based on a decision of the Court rendered in a nonprecedential opinion or order.

ECOLOCHEM, INC., Plaintiff-Appellant, v. SOUTHERN CALIFORNIA EDISON COMPANY, Defendant-Appellee.

United States Court of Appeals, Federal Circuit.

Decided June 5, 1996.

Rehearing Denied; Suggestion for Rehearing In Banc Declined

July 30, 1996.

Before NEWMAN, MICHEL and CLEVENGERS, Circuit Judges.

MICHEL, Circuit Judge.

Decision

Ecolochem, Inc. (Ecolochem) appeals the summary judgment of the U.S. District Court for the Central District of California, No. CV 92-3436 RG, finding claims 1, 2, 5 and 6 of U.S. Patent No. 4,556,492 (the '492 patent) anticipated, and holding claims 7 and 10 of the '492 patent and claim 20 of U.S. Patent No. 4,818,411 (the '411 patent) obvious. The appeal was submitted for decision after oral argument on December 7, 1995. We affirm the findings of anticipation and the conclusions of obviousness of claims 7 and 10 of the '492 patent, but reverse the conclusion of obviousness of claim 20 of the '411 patent and remand for further proceedings.

I. Background

Ecolochem combined the Houghton process with an ion exchange resin to remove excess hydrazine and carbon contaminants and was awarded two patents based on this invention, the '492 patent and the '411 patent (a continuation of the '492 patent application). As prior art, the examiner cited references to applications of the Houghton process and the known use of hydrazine to deoxygenate liquid. In addition, with respect to the '411 patent, the examiner cited references, including Akol'zin, that teach the use of filters and ion exchange resins to remove liquid contaminants. Claim 1 of the '492 patent reads:

1. a deoxygenation process comprising a first step of adding hydrazine to a liquid containing dissolved oxygen, a second step of passing said liquid through a bed of activated carbon to catalyze a reaction between said dissolved oxygen and said hydrazine whereby an amount of dissolved carbon contaminants are added to said liquid, and a third step of passing said liquid through an ion exchange resin selected from the group consisting of mixed bed resin and cation resin to remove at least said dissolved contaminants.

(Claims 2, 5, and 6 are dependent on independent claim 1; claim 7 is dependent on claim 6; claim 10 is dependent on claim 9 which is dependent on independent claim 8.) Claim 1 recites three basic steps: 1) adding hydrazine to a liquid containing dissolved oxygen, 2) catalyzing the reaction between the dissolved oxygen and the hydrazine using activated carbon, and 3) removing dissolved carbon contaminants with an ion exchange resin. Claim 2 adds a filtration step to remove undissolved carbon contaminants; claim 5 recites the additional removal of unreacted hydrazine through the ion exchange resin; claim 6 limits the liquid of claim 1 to water; claim 8 is similar to claim 1 but requires the removal of excess hydrazine in the third step, not the dissolved carbon contaminants; and claims 7 and 10 add a final step of circulating the deoxygenated water at elevated temperature conditions in a power generating apparatus. Claim 20 of the '411 patent is similar to claim 1 of the '492 patent but omits the first step of the process, taking into account that hydrazine may already be present, and claims the removal of dissolved carbon contaminants with both cation and anion exchange resins in series. On Southern California Edison Co.'s (Edison) motion for summary judgment, the district court found that claims 1, 2, 5 and 6 of the '492 patent are anticipated by Demmitt, a reference not considered by the examiner during prosection of the application leading to the issuance of the patents in suit, and held that, in light of Demmitt, claims 7 and 10 of the '492 patent and claim 20 of the '411 patent are obvious under 35 U.S.C. § 103. ¹ Ecolochem appeals from the judgment based on these findings and conclusions which it challenges.

II. Standard of Review

We review the district court's grant of summary judgment de novo, resolving all doubts respecting the presence or absence of genuine factual issues in the nonmovant's favor. Bell Communications Research, Inc. v. Vitalink Communications Corp., 55 F.3d 615, 619, 34 USPQ 2d 1816, 1819 (Fed.Cir.1995). Proper claim construction is a question of law which we review de novo. Markman v. Westview Instruments, Inc. 52 F.3d 967, 979, 34 USPQ2d 1321, 1329 (Fed.Cir.1995) (in banc), aff'd, 116 S.Ct. 1384 (1996).

III. Anticipation

It is undisputed that the Demmitt reference discloses an application of the Houghton process followed by the use of a cation exchange resin to remove hydrazine from the liquid. The reference does not disclose that carbon contaminants are added to the liquid by the Houghton process, nor does it indicate the desirability of removing those dissolved carbon contaminants. By its very nature, however, the cation resin removes cationic dissolved carbon contaminants. Furthermore, it is agreed by the parties that most, if not all, carbon sources used in the Houghton process would leach anionic as well as cationic contaminants. Since anticipation is shown where each and every limitation of the claimed invention is found in a single prior art reference, In re Donohue, 766 F.2d 531, 534, 226 USPQ 619, 621 (Fed.Cir.1985), Demmitt anticipates claim 1 if that claim requires only the removal of dissolved cationic carbon contaminants, rather than all of the dissolved carbon contaminants, both cationic and anionic.

A claim is construed by looking at the language of the claim, other claims in the patent, the specification and, where in evidence, the prosecution history. Markman, 52 F.3d at 979, 34 USPQ2d at 1329. Claim 1 recites a "deoxygenation process comprising a first step of adding hydrazine ... a second step ... [where] carbon contaminants are added ... and a third step of passing said liquid through an ion exchange resin selected from the group consisting of mixed bed resin and cation resin to remove at least said dissolved contaminants." Ecolochem argues that it is clear from the language of the claim itself, the specification, and the prosecution history of the patent that claim 1 recites a process including a limitation that all dissolved carbon contaminants are to be removed by the ion exchange resin.

Analyzing the language of the claim, we observe that step three of claim 1 is written in the alternative using the Markush format. By claiming a Markush group, Ecolochem has indicated that, for the purpose of claim validity, the members of the claimed group are functionally equivalent. Thus, if utilizing one element of the group is anticipated or obvious, the patentee is precluded from arguing that the claim is valid. See In re Skoll, 523 F.2d 1392, 1397, 187 USPQ 481, 484-85 (CCPA 1975). Accordingly, if either alternative in the Markush group of step three, i.e., employing a cation resin or a mixed bed resin, is anticipated, the entire claim is anticipated.

Demmitt clearly discloses the use of the Houghton process on oxygenated water followed by use of a cation exchange resin. As discussed above, Demmitt meets all the limitations of one of the claimed alternatives in claim 1 of the '492 patent (i.e., using a cation exchange resin to remove dissolved contaminants). Accordingly, it would appear that claim 1 is anticipated by Demmitt.

Ecolochem argues, however, that, despite the recitation of a cation exchange resin as an element of the Markush group, there is a limitation in the claim requiring that all dissolved carbon contaminants be removed. This result can be accomplished, Ecolochem claims, by the use of a mixed bed resin or by the use of a cation resin in combination with an anion resin, and since claim 1 is written using the open-ended term "comprising," the claim should be construed to include the use of additional elements, i.e., addition of an anion resin to follow the cation resin of the second alternative. Placement of "comprising" before recitation of steps, however, results in a "comprising" claim that would cover a process that includes additional steps, not one that uses an additional unrecited element for accomplishing a claimed step. See Moleculon Research Corp. v. CBS, Inc., 793 F.2d 1261, 1271, 229 USPQ 805, 812 (Fed.Cir.1986), cert. denied, 479 U.S. 1030 (1987) ("While a transitional term such as 'comprising' or, as in the present case, 'which comprises,' does not exclude additional unrecited ... steps ... we conclude that the transitional phrase does not ... affect the scope of the particular structure recited within the method claim's steps.") Thus, all the claim requires, in step three, is that either a mixed bed resin or a cation exchange resin be used exclusively to achieve the stated goal of removing dissolved carbon contaminants added in step two. In sum, a patentee may not import additional limitations into the steps of a process claim merely by using the word "comprising" in the claim preamble. Accordingly, claim 1 is anticipated by Demmitt. ²

Because Demmitt clearly discloses the use of water as the liquid to deoxygenate and that the cation exchange resin can be used to remove excess hydrazine, claims 5 and 6 of the '492 patent are anticipated by Demmitt as well. It is unclear why claim 2, which also calls for the removal of undissolved contaminants, was found to be anticipated by Demmitt. In any event, because Ecolochem fails to distinguish claim 2 from claim 1 for purposes of anticipation, we also affirm the finding on summary judgment that, on the undisputed facts, Demmitt anticipates claim 2. ³

IV. Obviousness

A. Claims 7 and 10 of the '492 Patent

The...