Click here for our latest news and resources on COVID-19

News & Events


Why Software Owners Should Welcome a Recent Federal Circuit Decision

By Procopio Partner Noel C. Gillespie

We’ve seen many developments in recent years that have weakened patents or made them easier to invalidate, which have led to increasing confusion as to what is actually patentable, and how a claim will be construed once it is challenged. That’s why patent owners—in particular companies patenting software-related innovations—should take solace in a recent Federal Circuit decision that could bring much-needed clarity to how a claim will be construed. This is welcome news to beleaguered patentees and to our very important innovation economy.

The Federal Circuit’s recent decision in Zeroclick, LLC, v. Apple Inc., (Fed. Cir. 2017) provides potential relief and welcomed guidance, particularly for software companies. Two patents were at issue, U.S. Patents 8,549,443 and 7,818,691, covering improvements for a Graphical User Interface (GUI) that allow the user to provide input to a device via pre-defined pointer or touch movements as opposed to mouse clicks. The district court found the asserted claim invalid for indefiniteness, first finding that several limitations in the asserted claims were in fact means-plus-function limitations and then finding that the specification did not disclose sufficient structure for performing the claimed functions. 

On appeal, the Zeroclick panel overturned the finding of indefiniteness because the district court did not undertake the proper factual inquiry in determining the limitations in question were means-plus-function limitations. But in so doing, the panel gave important guidance that can be used by not just GUI developers, but software developers in general to ensure their claim limitations are not found to be means-plus-function limitations.

Having a claim interpreted to include means-plus-function limitations is not necessarily a bad thing and can even be advantageous. But typically the scope of such claims is narrower than non-means-plus-function claims. As such, having a claim interpreted to include means-plus-function limitations, when that was not the intent of the patent owner can have a negative effect. That’s especially true if enforcement of the claim has been commenced under the assumption the claims do not include means-plus-function limitations.

A typical means-plus-function claim limitation arises when the terms “means” or “means for” are followed by the function performed, without detailing the structure used to perform the function. The Supreme Court had at one time ruled that such claims were invalid. But Congress specifically overturned this precedent and codified the ability for a patentee to claim elements of a combination in terms of what they do as well as in terms of what they are; however, the claim scope is limited, for both purposes of enforcement and examination, to the corresponding structure, material or acts described in the specification for performing the claimed function or equivalents thereto. Thus, the ability to use the means-plus-function form allows the patentee greater leeway to broadly claim the functions being performed, although the claim will be more narrowly construed to cover only those structures actually disclosed for performing the functions and equivalents thereto. See 35 U.S.C. 112(f) or Pre-AIA 35 U.S.C. 112, Sixth Paragraph.

The availability of such functional claiming was historically important in convincing the courts of the patentability of software inventions. Also, the statutory inclusion of equivalent structures can provide insurance against loss of equivalence coverage in the event a claim is amended during prosecution*. But due to the likely narrower claim scope, patentees typically still seek more conventional (i.e., non-means-plus-function) claims. 

In the case of a software invention, however, the only structure is typically a processor that is configured to run various programs that cause the processor to carry out various functions. Often, patent drafters will use such terms as “module”; “unit”; “engine”; “element”; etc., to describe the combination of hardware and software that perform these various functions. Accordingly, software patents often include claim limitations in the form of, for example: “an imaging module configured to generate an image by . . . ;” “an imaging unit configured to generate an image by. . .;” or  “an imaging engine configured to generate an image by . . . .” 

Because such claim limitations do not use the term “means” or “means for”, they are presumed to not be and were rarely construed as means-plus-function limitations. But all that was potentially changed by the Federal Circuit’s 2015 decision in Williamson v. Citrix Online LLC, 792 F.3d 1339 (Fed Circ. 2015) (en banc).  Prior to Williamson, it was well-established that, while not dispositive of the issue, the use of the term “means” or “means for” created a presumption the claim limitation at issue should be interpreted as a means-plus-function limitation. 

Conversely, a lack of such terms creates a presumption that the claim limitation is not a means-plus-function limitation. Moreover, case law had also established that this later presumption, against a means-plus-function interpretation, was a strong one. Thus, under prior case law it was difficult for a challenger to overcome the presumption and have the claim interpreted as a means-plus-function claim. But the Federal Circuit undid this in Williamson, ruling that the presumption was not in fact a strong one, thereby lowering the bar to overcome the presumption and have a claim interpreted as including a means-plus-function limitation.

The reason this is significant is two-fold. First, as noted, means-plus-function limitations are often more narrowly construed, making it potentially easier to avoid infringement. Second, a defendant or challenger to the patent will often attempt to have a claim interpreted as a means-plus-function claim and then argue that the specification does not disclose sufficient structure for carrying out the claimed function(s), thereby rendering the claim invalid for being indefinite, which is exactly what happened both in Williamson and in the lower court decision in Zeroclick.  This lowering of the bar creates uncertainty as to how claims will be interpreted, which affects the scope of the claims, potentially making it easier to invalidate the claims and/or avoid infringement.

For example, in Williamson, one of the claim limitations at issue was the following:

“a distributed learning control module for receiving communications transmitted between the presenter and the audience member computer systems and for relaying the communications to an intended receiving computer system and for coordinating the operation of the streaming data module.”

The court noted that the function at issue resided within what the patent(s) at issue referred to as a “distributed learning server.” The specification made clear that the functionality of such a server could be “performed by software or hardware modules within the computer systems. The modules according to one embodiment are software programs stored on the storage device 208, loaded into the memory 206, and executed by the processor 202.” See ‘849 Patent, Col. 4, lines 43-48.  Thus, the specification appeared to provide a description of the structure for performing the functions. But the court determined the disclosure of a specific algorithm for performing the function on, or by the computer system was also required. The court went on to find that no such algorithm was disclosed for the coordinating operation in the limitation above. 

The Zeroclick decision applied Williamson but overruled the lower court’s finding that the claim limitations at issue were means-plus-function limitations. An important takeaway from the decision is that the district court failed to undertake the appropriate inquiry and make related factual findings to support its conclusion that the asserted claims recited means-plus-function terms. In essence, the court emphasized that it is improper to remove terms from their context and then conclude that stripped of that context, the terms convey no structure.  Rather, a factual inquiry has to take place to determine whether the claim limitations in the context of the claim and in light of the specification convey to one of skill in the art the structure for carrying out the claimed functions. This would seem to, or at least potentially, raise the bar somewhat to finding that a claim includes means-plus-function limitations. But, as importantly, the decision provides helpful practice tips that can be used to help ensure that claims are not interpreted as means-plus-function claims, when that is not the intent.

The court noted that the terms “user interface code” and “program” used in the claims identified specific code or programs stored in memory and executed by a processor and that one of skill in the art would, or at least could, reasonably conclude that the terms are not used as generic terms or black box recitations of structure or abstractions, but rather a specific references to a conventional graphical user interface programs or code  . . . .”  Thus, practitioners can use the form of the claims at issue and with respect to these terms as a possible template for avoiding a finding that the claims include means-plus-function limitations.

No single court decision can completely shift the landscape of intellectual property protection and litigation. But given the critical importance patents play in the global innovation economy, it’s worth taking a moment to note when a favorable court decision comes along that provides potential benefits for patent owners and positions them to better monetize their intellectual property and advance with further innovation.


* While patent claim language traditionally defines the patent right, the doctrine of equivalents (DOE) occasionally allows for a finding of infringement even when an accused product falls outside the literal limits of claim language.  More particularly, DOE applies when a claim limitation differs insubstantially from the accused product or if the accused element performs the substantially same function in substantially the same way with substantially the same result (function/way/result test).  A narrowing claim amendment made during prosecution creates a presumption that the element should be narrowly interpreted — legally precluding application of the DOE.

Noel C. Gillespie is a Partner with Procopio and formerly served on the firm’s Management Committee. He advises start-up and emerging growth clients on strategic patent portfolio development and implementation to protect their technology and achieve their business objectives, the most important objectives being market share and premium pricing. Noel’s approach to patent portfolio development helps his clients ensure their patents guard these important objectives, even on a budget.  Noel worked as an electrical engineer for many years, leading teams in the development of man-worn free space optical communication systems and early CDMA cellphones before attending law school and becoming a patent attorney. He has extensive experience working with telecommunications companies, especially wireless telecommunications companies; digital health, health information technology, and medical device companies; semiconductor; and software and Internet companies.