U.S. Supreme Court Won’t Hear Cialis Patent Suit Against Indiana’s Eli Lilly


Washington, D.C. – The United States Supreme Court denied certiorari in an appeal from three Vanderbilt University scientists who claimed that they should share ownership of the patent rights to Cialis. The Cialis patents in question, U.S. Patent numbers 5,859,006 and 6,140,329, were filed by Icos Corporation, which was acquired by Indiana-based Eli Lilly in 2007. According to coverage by the Indianapolis Star, Cialis sales exceeded $400 million in the third quarter of 2010.

The three scientists researched phosphodiesterase enzyme (“PDE5”), the active ingredient in Cialis, and claimed that they were joint inventors of Cialis. The scientists performed initial identification of and research on PDE5. This initial research was funded by Glaxo Inc., which later sold the rights to Icos Corporation. Patent attorneys for the scientists filed a lawsuit in the U.S. District Court of Delaware alleging that the scientists should be added to the patents as joint inventors. The district court, however, granted judgment in favor of Icos. Attorneys for the scientists appealed. The Court of Appeals for the Federal Circuit affirmed and clarified the statutory standard for joint ownership of a patent in their written opinion. The court stated “a group of co-inventors must collaborate and work together to collectively have a definitive and permanent idea of the complete invention.” The court concluded that the scientist had failed to show this. Patent attorneys for the scientists sought review by the U.S. Supreme Court, which has now declined to hear the case.

Practice Tip: In order to meet the requirements of joint inventorship for a patent, a plaintiff must show that he contributed to “the conception of the claimed invention.” As this case shows, it is not enough to merely provide some of the building blocks of an eventual invention.

The case is Vanderbilt University v. Icos Corporation and docket number in the U.S. Supreme Court was 10-412.

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