35 USC 121 Only Protects Divisional Applications, Not C-I-P's, From Double Patenting

Pfizer Inc., v. Teva Pharmaceuticals USA, Inc., [2007-1271] (March 7, 2008) [DYK, Michel, Kennelly] The Federal Circuit reversed the district court, and held that the asserted claims of U.S. Patent No. 5,760,068 were invalid based on double patenting, but affirmed validity, enforceability and infringement of U.S. Patent Nos. 5,466,823 and 5,563,165.
BRIEF: After a restriction requirement in the application that resulted in the '823 patent, Pfizer Pfizer filed a divisional application, which ultimately issued as the ’165 patent, that included the restricted-out composition claims, and a continuation-in-part application ("CIP"), which ultimately issued as the ’068 patent, that included the restricted-out method claims. Teva challenged the '068 as invalid for double patenting, and Pfizer responded that the patent was protected by the safe harbour of 35 USC 121. The Federal Circuit observed that Section 121 explicitly refers to "divisional applications," and held that the safe harbor, by its literal terms, protects only "divisional application[s]" (or the original application) and patents issued on such applications. The Federal Circuit also said that there is no suggestion, however, in the legislative history of section 121 that the safe-harbor provision was, or needed to be, directed at anything but divisional applications. The Federal Circuit concluded that the protection afforded by section 121 to applications (or patents issued therefrom) filed as a result of a restriction requirement is limited to divisional applications.