Means Plus Function Claims: Cafc Holds Structure Sufficient Where Specification Recites Algorithm In Prose

Typhoon Touch Technologies, Inc. ("Typhoon") sued Dell, Inc., and other manufactures of laptop computers and handheld devices for patent infringement of two patents directed to a portable, keyboardless computer. Typhoon Touch Tech., Inc. v. Dell, Inc., No.6:07-cv-00546-LED, (E.D. Tex. July 23, 2009) (Davis, J.). Defendants argued in defense that they did not infringe and that Typhoon's means plus function claims were invalid as indefinite for failing to satisfy the requirements of 35 U.S.C. § 112 ¶ 2. Specifically, defendants argued that Typhoon's patent specification failed to provide sufficient structure for its "means for cross-referencing" term in its asserted claims. The district court agreed and thus held Typhoon's claims invalid. Typhoon Touch Tech., Inc. v. Dell, Inc., No.6:07-cv-00546-LED, 2009 U.S. Dist. LEXIS 64013 (E.D. Tex. July 23, 2009). Typhoon appealed this decision. Typhoon Touch Tech., Inc. v. Dell, Inc., Case No. 2009-1589 (Fed. Cir. November 4, 2011).

On appeal, and as discussed herein, the CAFC focused its means plus function analysis on whether the patent specifications "contain[ed] sufficient descriptive text by which a person of skill in the field of the invention would 'know and understand what structure corresponds to the means limitation.'" Slip Op. at 13-14 (quoting Finisar Corp. v. DirecTV Grp., Inc., 523 F.3d 1323, 1340 (Fed. Cir. 2008)).

Consistent with the breadth to be afforded the meaning of "algorithm"

Precedent and practice permit a patentee to express that procedural algorithm "in any understandable terms including...