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"Vulnerability" of A Patent Insufficient To Contest A Preliminary Injunction

Client Alert | 1 min read | 11.07.08

A divided Federal Circuit panel, in Abbott Laboratories v. Sandoz, Inc. (No. 07-1300; October 21, 2008), affirms a preliminary injunction against accused infringer Sandoz, Inc. ("Sandoz"), holding that Abbott Laboratories ("Abbott") demonstrated, inter alia, that it will likely succeed at trial against Sandoz's claim that Abbott's patents are invalid for obviousness under 35 U.S.C. § 103(a).

Plaintiff-Appellee Abbott brought suit against Sandoz for patent infringement, charging that Sandoz's clarithromycin product infringed U.S. Patent No. 6,010,718 ("the '718 patent") and U.S. Patent No. 6,551,616 ("the '616 patent"), and moved for a preliminary injunction. In response, Sandoz asserted, inter alia, that both the '718 and '616 patents were invalid for obviousness. The district court applied the 4 factors relevant to the grant of a preliminary injunction, (1) the likelihood of success on the merits, (2) whether irreparable harm is likely if the injunction is granted, (3) the balance of hardships of the litigants, and (4) the public interest, and granted Abbott's motion for preliminary injunction. On appeal, Sandoz argued, inter alia, that the district court erred in finding that Abbott would likely prevail on the merits of the case as the patents were obvious. The Federal Circuit concludes that the district court properly applied the law of KSR International Co. v. Teleflex, Inc., 127 S.Ct. 1727 (2007), in determining that the patents were not rendered obvious by the prior art.

With respect to the issue of invalidity of the patents, the Federal Circuit notes that "[t]he question is not whether the patent is vulnerable; the question is who is likely to prevail in the end, considered with equitable factors that relate to whether the status quo should or should not be preserved while the trial is ongoing. The presentation of sufficient evidence to show the likelihood of prevailing on the merits is quite different from the presentation of substantial evidence to show vulnerability." In dissent, Judge Gajarsa argues that Federal Circuit precedent requires a preliminary injunction be denied when substantial questions of validity are raised.

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