In re Hilmer (Hilmer II)

Hilmer (plaintiff) filed a patent application that was rejected by the patent examiner as obvious. The rejection was based on two patent references, one having been filed in the United States prior to Hilmer’s application, but the other (the Habicht patent) having been filed in the United States after Hilmer’s filing date. The Habicht patent, however, relied upon a foreign-filed patent application (the Switzerland application) for priority. The Switzerland application’s filing date pre-dated Hilmer’s United States application filing date. Hilmer appealed the examiner’s decision to the Patent Office Board of Appeals (Board), which upheld the rejection, holding that a U.S. patent is prior art as of its foreign filing date. In In re Hilmer (Hilmer I), 359 F.2d 859 (C.C.P.A. 1966), the United States Court of Customs and Patent Appeals reversed the Board’s decision. The court held that the Habicht patent constituted prior art under 35 U.S.C. § 102(e) only as of Habicht’s filing date in the United States, and that Hilmer could overcome this prior art date because he had filed a patent application in Germany before Habicht filed in the United States. On remand, the Board considered the question of whether the compound claimed in claim 1 of the Habicht patent was prior art that would support rejecting the Hilmer application as obvious. Relying primarily on 35 U.S.C. § 102(g), the Board concluded that the claim 1 compound was patent-defeating prior art against Hilmer as of the date of Habicht’s Switzerland application. Hilmer appealed.