The patent statute (35 USC § 121) indicates that divisional patent applications cannot be receive a double patenting rejection based on claims of a parent application. This is commonly known as the safe harbor provision of Section 121.
The following case illustrates whether the safe harbor applies to a patent application that is a divisional in “substance” but “designated” a continuation in the application’s documentation. In Amgen Inc. v. F. Hoffman-La Roche Ltd (Sept. 15, 2009), the Federal Circuit held that a patent application “designated” as a continuation patent application (even if in “substance” it qualifies as a divisional patent application) does not fall within the safe harbor provisions of 35 U.S.C. § 121. The Federal Circuit also highlighted a similar case in which a continuation in part (“CIP”) application does not fall within the safe harbor provisions of 35 USC § 121. Pfizer, Inc. v. Teva Pharmaceuticals USA, Inc. 518 F.3d 1353 (Fed. Cir. 2008).
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