Therasense, Inc. v. Becton, Dickinson & Co.

Therasense, Inc. v. Becton, Dickinson & Co.

Opinion

 [***1482]  [*1328]   LINN, Circuit Judge.

Abbott Diabetes Care, Inc. and Abbott Laboratories (collectively "Abbott") appeal the final decision of the U.S. District Court for the Northern District of California, which entered judgment in accordance with a jury verdict that claims 11 and 12 of Abbott's U.S. Patent No. 5,628,890 ("the '890 patent") are infringed by Becton, Dickinson & Co. and Nova Biomedical Corp. (collectively "BD/Nova") but are invalid under 35 U.S.C. §§ 102, 103, and 112 P 1, and denied Abbott's post-trial motions for judgment as a matter of law ("JMOL") and for new trial. Therasense, Inc. v. Becton, Dickinson & Co., No. 04-CV-2123 (N.D. Cal. Sept. 2, 2008). [**2]  Although judgment was entered in favor of BD/Nova on all counts relating to the '890 patent, BD/Nova cross-appeals the jury's underlying finding that it infringes claims 11 and 12. Because we conclude that the district court did not err in denying Abbott's post-trial motions on invalidity, and because we lack jurisdiction over BD/Nova's cross-appeal, we dismiss the cross-appeal and affirm the judgment.

BACKGROUND

The '890 patent is directed to electrochemical sensors for measuring glucose levels in blood. A droplet of blood is placed on a disposable test strip that has two electrodes: a "working electrode" and a "counter electrode." The working electrode is coated with an enzyme and a mediator. The enzyme serves as a catalyst to facilitate a chemical reaction in which the glucose molecules in the blood sample lose some of their electrons, and the mediator then transfers those electrons to the working electrode. As the electrons flow through the working electrode, an electrical current is detected. The magnitude of the electrical current can then be correlated to the concentration of glucose molecules in the blood. The electrons  [**3] are then brought back into the blood through the counter electrode. To complete this circuit, the blood must be in contact with both electrodes at the same time.

A problem occurs, however, if the blood only partially covers the working electrode. For example, if too little blood is  [*1329]  supplied, or if the test strip is not held in a horizontal position, the blood may not fully cover the working electrode, resulting in the production of fewer free electrons. Because fewer electrons will flow between the two electrodes, the sensor will report an erroneously low glucose level. Based on this false reading, a patient may fail to take insulin when he should, or the patient may consume carbohydrates when he should not.

Full case includes Shepard's, Headnotes, Legal Analytics from Lex Machina, and more.