Most software inventions are functional in nature.  The focus is not on what the invention is so much as what it does.  The same physical hardware can be programmed by way of software to carry out an infinite number of different operations.  Thus, it is not uncommon for software inventions to be claimed as methods.  But when such inventions are claimed from the point of view of hardware carrying out a method, the patentee runs the risk of the claims being interpreted under 35 U.S.C § 112(f) (pre-AIA § 112 paragraph 6) as being in "means-plus-function" form.  This, of course, can effectively narrow the scope of the claims to embodiments disclosed in the specification and equivalents thereof.  Also, such claims can be found invalid if the specification does not disclose sufficient structure to support the embodiments.

Zeroclick sued Apple in the Northern District of California, contending infringement of U.S. Patent Nos. 7,818,691 and 8,549,443.  The District Court concluded that the asserted claims invoked § 112(f), lacked the necessary structure, and were thus invalid.  Zeroclick appealed.

As stated by the Federal Circuit "[t]he '691 and '443 patents relate to modifications to the graphical user interfaces of devices such as computers and mobile phones, modifications that allow the interfaces to be controlled using pre-defined pointer or touch movements instead of mouse clicks."  To that point, example claims of the '691 and '443 patents respectively recite:

2.  A graphical user interface (GUI), which may comprise an update of an existing program, that may fully operate a GUI by a two step method of movement of a pointer (0) to operate one or more functions within the GUI,
    wherein, said existing program is any existing program that can operate the movement of the pointer (0) over a screen (300) and has one or more functions operated by one or more other methods apart from said two step method, and/or one or more functions operated by said one or more other methods in said existing program can be updated to operate by said two step method,
    wherein said GUI executes one or more functions within the GUI by the completion of the following said two step method:
        first said pointer (0) is immediately adjacent or passes within a control area (1), which is an area of the screen (300) that may be any size including from a pixel on the screen (300) to occupying the whole screen (300), and
        second by the completion of a subsequent movement of said pointer (0) according to a specified movement generates a 'click' event, thereby triggering one or more functions within the GUI.

19.  A device capable of executing software comprising:
    a touch-sensitive screen configured to detect being touched by a user's finger without requiring an exertion of pressure on the screen;
    a processor connected to the touch-sensitive screen and configured to receive from the screen
    information regarding locations touched by the user's finger;
    executable user interface code stored in a memory connected to the processor;
    the user interface code executable by the processor;
    the user interface code being configured to detect one or more locations touched by a movement of the user's finger on the screen without requiring the exertion of pressure and determine therefrom a selected operation; and
    the user interface code is further configured to cause one or more selected operations, which includes one or more functions available to the user interface code of the device, to deactivate while the user's finger is touching one or more locations on the screen.

While construing the claims, the District Court stated that the features of a "program that can operate the movement of the pointer (0)" and "user interface code being configured to detect one or more locations touched by a movement of the user's finger on the screen without requiring the exertion of pressure and determine therefrom a selected operation" were properly interpreted under § 112(f).

In reviewing the District Court's holding, the Federal Circuit relied heavily on Williamson v. Citrix Online, LLC.  This case made it clear that:

To determine whether § 112, para. 6 applies to a claim limitation, our precedent has long recognized the importance of the presence or absence of the word 'means.'  The failure to use the word 'means' creates a rebuttable presumption that § 112, ¶ 6 does not apply.  But the presumption can be overcome, and § 112, ¶ 6 will apply, if the challenger demonstrates that the claim term fails to recite sufficiently definite structure or else recites function without reciting sufficient structure for performing that function.

Furthermore, "[w]hen evaluating whether a claim limitation invokes § 112, ¶ 6, the essential inquiry remains whether the words of the claim are understood by persons of ordinary skill in the art to have a sufficiently definite meaning as the name for structure."  This inquiry is to consider factual evidence both intrinsic and extrinsic to the patent.  The Federal Circuit's main beef with the District Court is that the latter failed to carry out the inquiry or make any factual findings.

Notably, neither of the features that the District Court interpreted under § 112(f) used the word "means," which gives rise to the presumption that § 112(f) does not apply.  Nonetheless, "Apple argued that the limitations must be construed under § 112, ¶ 6, but provided no evidentiary support for that position . . . [a]ccordingly, Apple failed to carry its burden, and the presumption against the application of § 112, ¶ 6 to the disputed limitations remained unrebutted."

Similarly, the District Court also failed to rebut the presumption, as "its determination that the terms must be construed as means-plus-function limitations is couched in conclusory language" and relied on Apple's arguments without providing any supporting evidence for its conclusion.

The District Court's specific language included the statements:

The Court concludes that the term 'program that can operate the movement of the pointer (0)' is a means-plus-function term because the claim itself fails to recite any structure whatsoever, let alone 'sufficiently definite structure.'

and

Because the use of the phrase 'user interface code' provides the same 'black box recitation of structure' as the use of the word 'module' did in Williamson, and the claim language provides no additional clarification regarding the structure of the term, the Court concludes that 'user interface code' constitutes a means-plus-function term.

According to the Federal Circuit, the District Court erroneously "treated 'program' and 'user interface code' as nonce words, which can operate as substitutes for 'means' and presumptively bring the disputed claims limitations within the ambit of § 112."  The appeals court found three distinct problems with doing so.

"First, the mere fact that the disputed limitations incorporate functional language does not automatically convert the words into means for performing such functions."  Notably, many structural components or devices are named after the functions they perform.

"Second, the court's analysis removed the terms from their context, which otherwise strongly suggests the plain and ordinary meaning of the terms."  Particularly, the terms "program" and "user interface code" were not used in the claim as nonce terms, but instead refer to "conventional graphical user interface programs or code, existing in prior art at the time of the inventions."  And as explained in the specifications, the claimed invention was an improvement to such interfaces and code.

"Third, and relatedly, the district court made no pertinent finding that compels the conclusion that a conventional graphical user interface program or code is used in common parlance as substitute for 'means.'"  The Federal Circuit suggested that use of a broader term, such as "module", in place of "program" and "user interface code" would have likely have invoked § 112(f).

For these reasons, the Federal Circuit reversed the District Court and remanded the case for further proceedings.

Zeroclick, LLC v. Apple Inc. (Fed. Cir. 2018)
Panel: Circuit Judges Reyna, Taranto, and Hughes
Opinion by Circuit Judge Hughes