Reiffin v. Microsoft: The Rise and Fall of the So-Called 'Omitted Elements Test'

Article by Linda J. Thayer, Jeffrey A. Berkowitz and Darrel C. Karl

Originally published in IP Litigator, September 2000

On June 5, 2000, the Federal Circuit reversed the lower court's summary judgment decision in Reiffin v. Microsoft Corp., 48 USPQ2d 1274, 1277 (N.D. Cal. 1998) ["Reiffin I"] and remanded the matter to the Northern District of California court for further determination as to whether the claims of the two patents at issue (U.S. Pat. Nos. 5,694,603 and 5,694,604) are invalid for failure to comply with the written description requirement of 35 U.S.C. § 112, first paragraph. Reiffin v. Microsoft Corp., No. 98-1502, 2000 U.S. LEXIS 12191, at *7 (Fed. Cir., June 5, 2000)(per curiam)["Reiffin II"]. In its per curiam opinion, the Court concluded that the lower court had erred by deciding whether the patents contained an adequate written description based on the original application filed in 1982, even though Reiffen had not claimed the benefit of the earlier application under 35 U.S.C. § 120. The Court stated that because the earlier date was not claimed, in this case, only the specifications of the later applications were relevant for purposes of § 112, ¶ 1.

In the coming months, the lower court will now revisit the issue of validity with a restricted focus on the later-file specifications of the two patents, both of which have the same specification and presumably share some content with the parent 1982 specification. The '603 patent claims a memory product storing multithreaded software, and the '604 patent claims a method of multithreaded operation and a multithreaded system. In 1985, Reiffin filed a continuation of the 1982 application and, in 1990, filed a continuation-in-part application of the 1985 application that contained additional text and modified claims and described the system as a "multithreaded computer application." Both the ?603 and ?604 patents issued on December 2, 1997 -- the ?603 patent from the 1990 continuation application and the ?604 patent from a continuation of the 1990 application that was filed in 1994. The claims of the '603 and '604 patents were amended several times during the lengthy prosecution. The validity determination on remand will likely hinge on whether the additional material in the 1990 application that was not present in the 1982 application provides sufficient detail to meet the requirements of the written description requirement of §112, ¶ 1.

This determination will bring the lower...

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