No. 42
June 2015

Follow us on:

International Association for the Protection of Intellectual Property

AIPPI General Secretariat |Toedistrasse 16 |P.O.BOX |CH-8027 Zurich
Tel. +41 44 280 58 80 | Fax +41 44 280 58 85 |
AIPPI logo
The Federal Circuit clarifies the Katz exception to the general rule requiring disclosure of algorithms for means-plus-function software claims
(Article by Kristin M. Whidby, Fried, Frank, Harris, Shriver & Jacobson LLP, Washington, D.C. U.S.A.)
EON Corp. IP Holdings LLC v. AT&T Mobility LLC, Case No. 2014-1392 (Fed. Cir. May 6, 2015).

EON brought suit, alleging infringement of a patent directed to software that operates together with a television to interconnect various interactive features of the television. EON Corp., slip op. at 4. The asserted claims contained eight disputed means-plus-function terms. One such term, for example, was “means controlled by replaceable software means operable with said operation control system for... reconfiguring the operating modes by adding or changing features and introducing new menus.” Id. at 5. After a series of hearings, the district court found that all eight means-plus-function terms were indefinite because no corresponding algorithm was disclosed in the specification. On appeal, the CAFC affirmed.

The CAFC began its analysis with the well-established rule “that the corresponding structure for a function performed by a software algorithm is the algorithm itself.” Id. at 7. The court previously defined an “algorithm” as a fixed step-by-step procedure for accomplishing a given result. See Typhoon Touch Techs., Inc. v. Dell, Inc., 659 F.3d 1376, 1385 (Fed. Cir. 2011). Thus, in general, a specification must disclose more than just a general-purpose computer or microprocessor whenever means-plus-functioning claiming is used for computer-implemented inventions. EON Corp., slip op. at 7.

There is one exception to this rule: “a standard microprocessor can serve as sufficient structure for ‘functions [that] can be achieved by any general purpose computer without special programming.’” Id. at 8 (quoting In re Katz Interactive Call Processing Patent Litig., 639 F.3d 1303, 1316 (Fed. Cir. 2011)). EON argued the phrase “special programming” implies that a certain level of complexity is required before an algorithm must be disclosed in the specification, and, consequently, an algorithm need not be disclosed if a person skilled in the art could easily implement the software function. The CAFC rejected EON's argument on two grounds.

First, the court held that the phrase “special programming” refers to any programming required so that the microprocessor can perform the claimed functions, regardless of complexity. Id. at 11. Thus, the Katz exception is very narrow and is limited to mean-plus-function claims that cover only those general functions that are “coextensive” with a microprocessor itself (such as “receiving,” “storing,” or “processing” data). Id. at 9. “All other computer-implemented functions require disclosure of an algorithm.” Id. at 11.

Second, the CAFC reiterated “a person of ordinary skill in the art plays no role whatsoever in determining whether an algorithm must be disclosed as structure for a functional claim element.” Id. at 12. Instead, the perspective of a person of ordinary skill in the art only becomes relevant when the question is whether a disclosed algorithm is adequate. Id. at 13.

Applying this guidance to the present case, the court held that the Katz exception was inapplicable to EON's patent. The eight disputed means-plus-function terms required “‘more than merely plugging in a general purpose computer.’” Id. at 9 (quoting Ergo Licensing, LLC v. CareFusion, 673 F.3d 1361, 1365 (Fed. Cir. 2012)). That is, the claim terms required “special programming” that would convert a general-purpose computer into a special purpose computer capable of performing the claimed functions. The lack of disclosure of an algorithm in the specification was therefore fatal, even if, as EON contended, a person of ordinary skill in the art was capable of devising some means to carry out the recited functions.

In sum, the Katz exception is extremely narrow and will not save patents that fail to disclose algorithms corresponding to mean-plus-function software claims in any but the most limited circumstances.