Claim Drafting Following Typhoon Touch: Interpreting Means-Plus-Function and Functionality Standards in the Software World
Posted in Patents

In a precedential decision, the Court of Appeals for the Federal Circuit (CAFC) recently interpreted means plus function claim construction under 35 U.S.C. §112 ¶ 6.  In Typhoon Touch Technologies v. Dell, Inc. and Lenovo, Inc. et al.1, the CAFC reiterated that an algorithm may be disclosed in any form, including prose or visual form, in order to satisfy 35 U.S.C. §112.  As was the case in Typhoon Touch, it is not necessary to disclose a mathematical algorithm even in the computer software world.  Furthermore, the CAFC elected to reaffirm the requirements for infringement of functional language – holding that an accused device must actually perform, or be programmed to perform, any functional language in the claim.

Typhoon Touch Technologies filed suit against a who’s-who of cell phone and tablet device manufacturers, including Dell, Inc., Lenovo (United States), Inc., Apple, Inc., Fujitsu, Inc., Toshiba America Information Systems, Inc., Panasonic Corporation of N.A., HTC America, Inc., and Palm, Inc.  The Eastern District of Texas court ruled in favor of the defendants finding noninfringement and invalidity of the two patents in suit (U.S. Patent No. 5,379,057 and U.S. Patent No. 5,675,362) for a Portable Computer with a Touch Screen.2  Judge Davis of the Eastern District found noninfringement based on a narrow construction of functional claim language terms including “memory for storage,” “processor for executing,” “operating in conjunction,” and “keyboardless.” Furthermore, Judge Davis found claims 8, 11, and 12 of the ‘057 patent containing the term “means for cross-referencing” indefinite for failing to distinctly claim the subject matter regarded as the invention.    

Means for Cross Referencing:
Judge Davis declared the means-plus-function element indefinite for failing to delineate an actual algorithm by which the cross-referencing is performed – a strict and narrow view of means-plus-function requirements.  Judge Davis relied on a trilogy of recent CAFC opinions seeming to require a heightened functional recitation for software patents – requiring the recitation of some algorithm.3

Writing for the three-member CAFC panel, Judge Newman overturned the district court’s ruling regarding the “means for cross-referencing” term.  Judge Newman specifically addressed the software community, writing that “computer code is not required to be included in the specification.”  This ruling provides some guidance to an industry that had been the target of recent CAFC opinions invalidating patents utilizing means-plus-function language.  The CAFC has required the disclosure of some corresponding structure for a means plus function element – as was required in the well-known In re Donaldson, Co., 16 F.3d 1189, 1195 (Fed. Cir. 1994)(en banc).  And as many people in the software industry know, recent CAFC precedents have applied the Donaldson standard to invalidate software patents where the disclosed structure is a computer programmed to implement an algorithm.  “The disclosed structure is not the general purpose computer, but rather the special purpose computer programmed to perform the disclosed algorithm.”  Finisar Corp. v. DirectTV Group, Inc., 523 F.3d 1323 (Fed. Cir. 2008).

While no mathematical algorithm was detailed by Typhoon in either specification, the cross-referencing process is described in the specification of both the ‘057 and ‘362 patents:  

Cross-referencing entails the matching of entered responses with a
library of possible responses, and, if a match is encountered,
displaying the fact of the match, otherwise alerting the user, or
displaying information stored in memory fields associated with
that library entry.

Judge Newman held that Typhoon’s disclosure of the above referenced four-step process was sufficient structure to satisfy 35 U.S.C. §112 ¶ 2 based on the definition of an algorithm as described in In re Freeman, 573 F.2d 1237 (defining an algorithm as a “step-by-step procedure for solving a problem or accomplishing some end.”).  The panel instructs that an algorithm can be disclosed “in any understandable terms including a mathematical formula, in prose, or as a flow chart, or in any other manner….”  The critical analysis is whether a person having ordinary skill would interpret the disclosure as the structure by which a function is performed.  Here, the defendant failed to point out any evidence that a person of ordinary skill would not understand how to implement this function, and the court points to the description above as a sufficient disclosure of the algorithm used.  

When drafting computer-implemented means-plus-function language, the applicant must be sure to provide some step-by-step procedure for performing the function.  However, the required detail disclosed in the step-by-step process appears to be minimal, falling short of any mathematical algorithms.

Functional Language:
Also, on appeal, the CAFC affirmed Judge Davis’s ruling that an accused device must meet the functional requirements of the claims by more than a “capable of” threshold, rather, the accused device must actually perform, or be configured or programmed to perform, the claimed functionality to meet the element-by-element standard of infringement.  The panel affirmed the district court rejecting Typhoon Touch Technologies’ assertion that the element-by-element analysis is satisfied if the device is merely “capabl[e] of being configured or programmed to perform the stated function, although not so structured in the device provided by [a] defendant.”4

By requiring actual configuration of a device to find infringement, hardware producers, especially those producing equipment utilizing general processors, can breathe a sigh of relief.  Typhoon’s position would have lowered the threshold to “capable of,” thus making many general processors, often capable of a wide array of functions with the right programming, at risk of infringing functionally claimed device patents.

In conclusion, inventors and practitioners should remain wary of means-plus-function for the myriad of reasons commonly cited.  However, the picture is now a little clearer for those in the software world as a result of the easy-to-achieve standard set forth in Typhoon Touch.

 1Typhoon Touch Technologies v. Dell, Inc.,  659 F.3d 1376 (Fed. Cir. 2011).
 2Typhoon Touch Technologies, Inc. v. Dell, Inc., No. 6:07-cv-00546-LED, 2009 U.S. Dist. LEXIS 64013 (E.D. Tex. July 23, 2009). 
 3Judge Davis cites Aristocrat Technologies Australia PTY Ltd. V. International Game Technology, 521 F.3d 1328, 1334 (Fed. Cir. 2008); Net MoneyIN, Inc. v. VeriSign, Inc., 549 F.3d 1359 (Fed. Cir. 2008); WMS Gaming, Inc. v. Int’l Game Tech., 184 F.3d 1339 (Fed. Cir. 1999). 
 4Typhoon Touch Technologies, 659 F.3d at 1380.

This advisory was prepared by Nutter's Intellectual Property practice. For more information, please contact your Nutter attorney at 617-439-2000.

This update is for information purposes only and should not be construed as legal advice on any specific facts or circumstances. Under the rules of the Supreme Judicial Court of Massachusetts, this material may be considered as advertising.

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