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The Specter of Indefiniteness: Recent Rulings Pose Further Challenges for Computer Software Patents

In 1980, the Supreme Court declared that “anything under the sun that is made by man” could be patented. At that time, the main challenge in getting a patent was to demonstrate how the claims were novel and inventive over the teachings of the prior art. But more recent court decisions now require a fiendishly difficult consideration of the “subject matter” of patent claims, which probably is fatal for most business method inventions and many inventions implemented in computer software. (The lecturing, sanctimonious tone of these decisions is a little grating, too.)

In June 2015, two decisions continued the recent trend in patent law by revising the law on “functional” claim language—that is, language that describes what something does, as opposed to “structural” claim language, what something is. There are various kinds of claims that can be used in a patent (device claims, method claims, etc.), and the United States Code governing patent law expressly permits functional claim language:

“An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.”

35 U.S.C. 112(b).

Such claims are referred to as means-plus-function claims. Until now, a patent claim using the magic word “means” signaled that what followed was a functional description rather than a structural one. And if the claim language did not recite any particular structure, the proper construction of a means-for claim element referred to “the corresponding structure, material, or acts described in the specification and equivalents thereof.”

Since computer software is not structural in the same physical way as an eggbeater or a swing set, the claims in a computer software patent will have mainly functional language rather than structural language. In WMS Gaming Inc. v. Int’l Game Tech, the Federal Circuit Court of Appeals in 1999 held that when a software claim is set forth in means-plus-function form, the functional language is understood to refer to a “corresponding structure” in the specification in the form of “a specific algorithm” for performing the function recited by the claim.

In other words, to prevent a claim from being deemed invalid for indefiniteness, the specification must recite a specific algorithm for each software means-for element recited by a claim or else the claim is invalid. On the other hand, the Federal Circuit later acknowledged in In re Katz (2011) that a standard microprocessor could serve as sufficient structure for some generic functions that could be achieved by any general purpose computer without special programming, for example, “processing,” “receiving,” etc.

Recently, the Federal Circuit significantly narrowed the applicability of In re Katz. In Eon Corp. IP Holding LLC v. AT&T Mobility LLC, the patentee, Eon, conceded that for some of the means-for claim elements at issue, the specification did not recite a specific algorithm as required by WMS Gaming. But, argued Eon, the various means-for claim elements could all be achieved by any general purpose computer without special programming, and hence, the “Katz Exception” should be applied. The Federal Circuit rejected that argument, concluding that the rule recited by WMS Gaming was broad and general, while the exception recited by Katz was narrow and limited, covering only a few of the most generic means-for claim elements.

Going forward post-Eon, it is important for patent applications for software related inventions to include “specific algorithm” material for each specific claim element. That would include flow charts and pseudocode that set forth specific details for accomplishing the function recited in each such claim element.

On appeal from an earlier Federal Circuit ruling, a dozen Federal Circuit judges rendered an en banc decision last month in Williamson v. Citrix that increased the likelihood that claims will be interpreted as having functional elements. Before Williamson, there was a “strong presumption” that without the word “means,” section 112(f) (or, old-style section 112, sixth paragraph) did not apply, and vice versa. Williamson reversed the existing precedent to remove that strong presumption.

Now, there is a plain “presumption” that the word “means” signals whether or not section 112(f) applies, a presumption that a challenger can overcome with evidence that demonstrates that a claim term fails to “recite sufficiently definite structure” or else recites “function without reciting sufficient structure for performing that function.”

The court further added that:

“Module” is a well-known nonce word that can operate as a substitute for “means” in the context of § 112, para. 6. As the district court found, “‘module’ is simply a generic description for software or hardware that performs a specified function.” Generic terms such as “mechanism,” “element,” “device,” and other nonce words that reflect nothing more than verbal constructs may be used in a claim in a manner that is tantamount to using the word “means” because they “typically do not connote sufficiently definite structure” and therefore may invoke § 112, para. 6.

The impact of Williamson lands squarely on computer software claims, and may well extend much further. In today’s world, there are many applications that can be implemented as some combination of hardware and software. Many patent claims are drafted that describe arrangements of various modules, mechanisms, elements, and devices, which commonly are described using functional language.

Before Williamson, there was a strong presumption that such claim terms were not means-for claim elements. Post-Williamson, they likely are. Since that was not the understanding or intent of the original claim drafter, it would not be surprising if the specification failed to recite the required specific structures for such means-for interpretations. That would make such claims invalid and unenforceable.

Interestingly, the patent at issue in Williamson included both method claims and system claims. The means-for discussion was only applied as to the system claims. The method claims remained valid even though their claim elements are recited wholly in functional language. Including method claims is a simple yet important prophylactic act to avoid the painful effects of the new means-for jurisprudence.

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