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Phrase in Claim Preamble Did Not Limit Claims Because It Was Duplicative of Language in the Body of the Claims

07-1201, -1239
April 11, 2008

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Last Month at the Federal Circuit - May 2008

Judges: Gajarsa, Linn, Dyk (author)

[Appealed from: E.D. Mich., Chief Judge Friedman]

In Symantec Corp. v. Computer Associates International, Inc., Nos. 07-1201, -1239 (Fed. Cir. Apr. 11, 2008), the Federal Circuit overturned the district court’s finding of SJ, noting that the terms of the claim’s preamble did not function as a claim limitation.

Symantec Corporation (“Symantec”) owns U.S. Patent No. 5,319,776 (“the ’776 patent”), which concerns a method of scanning for and detecting computer viruses embedded in data files that are downloaded or copied from a remote server onto a computer. The previous owner of the ’776 patent asserted claims 1-20 against Computer Associates International, Inc. (“CA”) for the development and sale of numerous antivirus software products, and Richard Levin intervened, claiming to be a co-inventor of the ’776 patent. But the district court made a SJ finding of noninfringement following construction of the claim terms “a method of screening the data as it is being transferred,” “computer system,” and “destination storage medium.”

Symantec appealed the construction of those claim terms. Primarily, Symantec challenged the district court’s construction of the phrase “a method of screening the data as it is being transferred,” found in the preamble of independent claim 1. The Federal Circuit found that it was clear that the claim phrase “as it is being transferred” was added to the preamble during prosecution to overcome the prior art at the same time that the phrase “prior to storage” was added to the body of the claim.

Nevertheless, the Court concluded that the prosecution history failed to demonstrate clear reliance on the preamble during prosecution to distinguish the claimed invention from the prior art. Instead, the Court found that the “as it is being transferred” language was merely duplicative of the “prior to storage” limitation that had been construed by the Federal Circuit in a prior appeal and, thus, did not deserve a narrower construction. The Court reasoned that “it is assumed that the preamble language is duplicative of the language found in the body of the claims or merely provides context for the claims, absent any indication to the contrary in the claims, the specification or the prosecution history.” Slip op. at 9-10. Thus, the Court determined that the preamble phrase was not a separate limitation.

Next, Symantec challenged the district court’s construction of the terms “computer” and “computer system.” Although the district court construed those terms as limited to a single computer, the Federal Circuit found that the specification did not reveal any special definition for the terms, and the ordinary meaning of those terms supported a broader construction that would include a system of multiple, interconnected computers.

Symantec also appealed the district court’s construction of the term “destination storage medium” as encompassing only a storage system residing within a stand-alone computer. The Federal Circuit found the district court’s construction too narrow because once the term “computer system” was properly construed, there was no reason to limit “destination storage medium” to a computer hard drive. Instead, the term was broad enough to include floppy drives and thumb drives in addition to hard drives.

Next, Symantec challenged the district court’s SJ of noninfringement by inducement. Symantec asserted that CA induces its customers to infringe the ’776 patent by using its EAV products in conjunction with a downloading program. Although Symantec did not offer direct evidence that a CA customer directly infringed the ’776 patent, the Court agreed that Symantec offered circumstantial evidence of CA encouraging its customers to use the EAV products with a downloading product. Moreover, the Court noted that CA’s customers could only use the EAV products in an infringing manner. Accordingly, the Court agreed that sufficient circumstantial evidence of direct infringement created an issue of material fact and remanded the issue to the district court.

Turning next to CA’s cross-appeal, the Federal Circuit addressed the district court’s grant of SJ that the doctrine of laches did not bar recovery for Symantec. Because CA prevailed on SJ of noninfringement at the district court, the Court pointed out that a determination in CA’s favor on appeal on the issue of laches would not affect the grant of SJ. The Court thus dismissed the cross-appeal as improperly filed.

Nevertheless, the Court considered CA’s arguments on laches as an alternative ground for sustaining the judgment of noninfringement. The Court noted that the previous owner of the ’776 patent, Hilgraeve, sent a warning letter of possible infringement to Cheyenne Software (“Cheyenne”), the then owner of antivirus software called Inoculan. Subsequently, CA acquired Cheyenne and rebranded the Inoculan product as one of its EAV antivirus products. The Court noted that CA did not establish that the Inoculan product was the same or similar product to the accused products. Since laches would only apply if the accused products were the same or similar to the Inoculan product, the Court agreed with Symantec that the SJ barring the defense of laches was not in error.

The Federal Circuit also agreed with the district court’s SJ finding that Levin had failed to establish a genuine issue of fact that he was a co-inventor of the ’776 patent because of insufficient corroborating evidence. Here, Levin presented a declaration that he contributed to the conception of the ’776 patent. In an attempt to corroborate that declaration, Levin provided co-inventor Gray’s day planner, an entry of which discussed a telephone call taking place between Levin and Gray. Although Levin insisted that he gave the idea for the method of the ’776 patent to Gray during that phone call, the Court disagreed, noting that the entry suggested that Gray and Levin discussed the state of the prior art. In addition, the Court found that Gray’s lack of technical expertise was irrelevant to the question of whether Levin was an inventor. Although Gray lacked technical expertise, there was no suggestion that the other co-inventors lacked technical expertise.

Next, the Court considered the SJ determination that Hilgraeve, the then owner of the ’776 patent, did not commit inequitable conduct to obtain the patent. CA relied on Gray’s declaration where he discussed his qualifications in the field of computer communications software. CA asserted that Gray’s recitation of his qualifications was false because he was a marketing person, not a software person having technical expertise. The Court disagreed because Gray did not describe himself as a software person having technical expertise. Instead, Gray described himself as a person “intimately familiar with the state of the art.” Slip op. at 26. Since nothing in the record contradicted Gray’s description, the Court did not find that the declaration was a misrepresentation.

Finally, the Court vacated and remanded the district court’s SJ finding of noninvalidity because of the Court’s constructions of the terms “computer,” “computer system,” and “destination storage medium.” The Court noted that the same claim construction applies for validity determinations as for infringement determinations and sent the issue back to the district court for reconsideration in view of the proper claim construction.