November 2015
Intellectual Property & Technology Law Journal
By Doris Johnson Hines
Authored by Doris Johnson Hines and Andrew G. Strickland
The en banc Federal Circuit in Williamson v. Citrix Online, LLC1 (Williamson) clarified when claim terms are subject to the "means-plus- function" requirements of 35 U.S.C. § 112, paragraph 6 (pre-AIA) (Section 112(6)). Under Section 112(6), an applicant can claim an element "expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof." The trade-off for such functional claiming is that the element will be construed as the corresponding structure described in the specification and its equivalents.2 In Williamson, the Federal Circuit rolled back its earlier holdings regarding the strength of the presumption attached to using the word "means" in a claim. Before Williamson, failure to recite "means," created a "strong" presumption, "not easily overcome," that Section 112(6) did not apply to the claim element, as explained in Lighting World Inc. v. Birchwood Lighting, Inc.3 The presumption was so strong that in Flo Healthcare Solutions, LLC v. Kappos, the Federal Circuit stated that it was unwilling to apply Section 112(6) to a claim element unless it was "essentially . . . devoid of anything that can be considered structure."4 Williamson expressly overruled the characterizations in Lighting World and Flo Healthcare of that presumption. Instead, Williamson holds that while the presumption still applies, it is no longer a "strong one" that is "not easily overcome." Demonstrating that the claim element recites a function without reciting sufficient structure for performing that function overcomes the presumption.5
While Williamson's holding appears clear, its implications are less so. The holding presents several questions, both substantive and procedural, about how courts will analyze claim elements alleged to invoke Section 112(6). Such questions include the following are explored below:
1. Whether the holding of Williamson addresses the Federal Circuit's concern that the "means" presumption is uncertain in meaning and application;
2. What is the standard of review attached to the "means" presumption;
3. Whether the "means" presumption invites greater deference to a district court concerning the application of Section 112(6) to functional claims without structural support in the specification; and
4. Whether one Williamson's holding further restricts patent claims directed to computer-implemented or software inventions.
The en banc court explained that one reason it overruled Lighting World and Flo Healthcare's heightened burden for the "means" presumption was because that burden was "uncertain in meaning and application." Judge Newman argued in her dissent, however, that the court's holding moves away from certainty.6
Section 112(6) states that a claim element can be "expressed as a means or step for performing a specified function."7 While the statute does not explicitly state that only the use of the words "means" or "step" invokes Section 112(6), including those words in the claim element at the very least suggests that the statute has been invoked. The clearest and most unambiguous signal that a claim element invokes Section 112(6) would be a bright line rule of law that only those elements including "means" or "step" invoked the provision. The Federal Circuit in Williamson rejected that approach—instead of providing a bright line rule regarding the use of "means," the changed presumption suggests that other terms may more easily fall within Section 112(6). That approach suggests the court is more concerned with the terms it believes should fall within the Section 112(6) rubric than with its automatic application depending only on whether the claims use the particular word "means."
In addition to Section 112(6) not explicitly requiring the use of "means" or "step," Section 112(6) does not explicitly identify a presumption that attaches to the use of those terms in a claim element. The historical evolution of Section 112(6) suggests that the statute refers to "means" because Congress enacted it in response8 to Halliburton Oil Well Cementing Co. v. Walker.9 There, patent claims directed to measuring the depth of oil wells included a claim element reciting a "means . . . for tuning said receiving means to the frequency of echoes from the tubing collars."10 The Supreme Court found the claim indefinite and invalid because the "means . . . for tuning . . . " was a functional limitation at the point of novelty.11 Such functional claiming was not legally permitted.
While the claims in Halliburton recited a "means for" element, the precedent relied on by the Supreme Court to decide Halliburton did not. So, introducing "means" in Section 112(6) may reflect Congress superseding Halliburton's holding as opposed to an indication that Section 112(6) will only be invoked by using the word "means." As Judge Reyna points out in his concurrence-in-part in Williamson, the rationale for the creation of Section 112(6) "applies to functional claiming in general, not just to claims that recite 'means.' "12
Similarly, history shows the rationale for attaching a presumption to the recitation of "means." The Federal Circuit remarked in Personalized Media Communications, LLC v. International Trade Commission,13 that "the use of the term 'means' has come to be so closely associated with 'means-plus-function' claiming that it is fair to say that the use of the term 'means' (particularly as used in the phrase 'means for') generally invokes [Section 112(6)] and that the use of a different formulation generally does not." This close association provides the rationale for attaching a presumption that using "means" invokes Section 112(6).
Why the presumption was elevated to a "strong" one is unclear. As the Williamson opinion acknowledges, Lighting World was the first time the Federal Circuit stated that the presumption associated with the absence of "means" in a claim element is a "strong one that is not readily overcome."14 Lighting World, however, does not explain why the presumption was strong. Instead, the Lighting World court merely observes that in past cases when claim terms failed to recite "means," Section 112(6) rarely applied. In other words, the results of past cases implied that the presumption was not easily overcome in practice. As cases continued citing Lighting World for the proposition that the presumption was strong and not easily overcome, it became more difficult for challengers to convince courts to apply Section 112(6) to non-means styled claims. This progression ultimately resulted in the Federal Circuit's statement in Flo Healthcare that it was unwilling to apply Section 112(6) to a claim element not reciting "means" unless that claim element is "essentially . . . devoid of anything that can be considered structure."15
Viewed with this historical background, returning the presumption to its pre-Lighting World state makes sense. Considering congressional intent when it added the language of paragraph 6 to the Section 112—to permit functional claiming provided such claim terms are construed as corresponding to the structure disclosed in the specification and equivalents—Lighting World and its progeny appear to have "shifted the balance struck by Congress in passing § 112 para. 6" and may have "plac[ed] a thumb on what should otherwise be a balanced analytical scale."16
Although Williamson's holding makes sense in the historical context, it may introduce uncertainty as to when Section 112(6) applies. This cuts against the en banc Williamson majority's criticism that the heightened burden previously associated with the "means" presumption is "uncertain in meaning and application." By weakening the presumption associated with using "means" in a claim element, more claims may be subject to Section 112(6), resulting in uncertain claim scope for many more claims than before Williamson. The public and patentees may not know whether claims are limited to the structure disclosed in the specification until a court decides that Section 112(6) applies.
In his concurrence-in-part, Judge Reyna questioned whether presumptions are the appropriate procedural mechanism to analyze the applicability of Section 112(6) to a claim term. In short, he suggested that under the language of the statute, no presumption attaches to a claim element's recitation, or failure to recite, "means." Instead, he opines that Section 112(6) provides one test for its applicability: "is the element 'expressed as a means or step for performing a specified function without the recital of structure, material or acts in support thereof.' "17 While discussing presumptions, he touched on an important aspect of Section 112(6) left unresolved by Williamson: the standard of proof attached to the presumption.
A presumption is a procedural tool for shifting the burden of proof on a particular issue. With a certain fact giving rise to the presumption, a court will accept the presumption's conclusion unless that conclusion is rebutted. Rebuttal comes in the form of evidence that meets or exceeds the standard of proof associated with the presumption. The standard of proof may determine whether a challenging party has rebutted a presumption. A familiar example from patent law is the presumption of validity associated with issued patents. To overcome that presumption, a challenger must present clear and convincing evidence that the patent is invalid. The standard attached is an important factor in a court's analysis—if a party challenging the validity of a patent only does so with a preponderance of evidence, the party has not overcome the presumption.18
While the standard of proof regarding the validity presumption is well-known, the standard of proof regarding Section 112(6)'s application is not. Before Williamson, the presence of "means" in a claim element gave rise to a "strong" presumption that Section 112(6) applied to the claim element. Yet Lighting World and its progeny were silent as to how that "strong" characterization affected the standard of proof. Indeed, Judge Reyna's Williamson concurrence-in-part questions this issue.19
Because under Lighting World, the Section 112(6) presumption was strong and not easily overcome, the appropriate standard of proof for rebutting the presumption should have been clear and convincing. While Williamson does not articulate a standard of proof, a reasonable assumption is a preponderance of evidence, the default standard of proof for civil cases and the standard of proof for proving infringement.20 A preponderance of evidence standard also seems appropriate given that Williamson removes the "strong" characterization from the presumption, that is, a "regular" presumption implies a preponderance of evidence standard.
However, using a preponderance of evidence standard for determining whether Section 112(6) applies to a claim element could lead to a situation in which patent claim validity is determined based on a preponderance of evidence standard, as opposed to the clear and convincing evidence standard. To understand when this situation might arise, consider the sources of evidence courts use to determine whether Section 112(6) applies.
When a court determines if Section 112(6) applies, it analyzes the claim element to determine if it is purely functional, that is, whether the claim element recites structure sufficient to perform the claimed function.21 If the claim term recites structure, Section 112(6) does not apply.22 This is true even if the claim element recites "means" triggering the presumption of Section 112(6) applicability—if the "means" element recites sufficient structure for performing the claimed function, Section 112(6) does not apply. But, the Federal Circuit has held that when a claim does not recite "means," but uses a means-substitute "nonce" word followed by functional language, courts should consider the specification to determine whether one of ordinary skill in the art would consider the means-substitute nonce word devoid of structure, thereby invoking Section 112(6).23 If the specification suggests the means-substitute connotes structure for performing the function, then Section 112(6) does not apply. Conversely, if the specification suggests the means-substitute does not connote structure for performing the function, then Section 112(6) applies. In these situations, the two-part validity test for Section 112(6) claim elements essentially collapses into one step: If the specification fails to support the means-substitute, not only will Section 112(6) apply to that claim term, but the claim term will likely be found invalid for indefiniteness because the specification fails to disclose corresponding structure for performing the claimed function.24
As a result, it is unclear which standard of proof is appropriate because each part of the two-part Section 112(6) validity test arguably has a different standard. If a court uses the clear and convincing standard to determine both Section 112(6) applicability and invalidity for a claim element, it would apply a standard of proof inconsistent with Williamson's holding that the Section 112(6) presumption is not strong. On the other hand, if the court uses a preponderance of evidence standard to determine the applicability of Section 112(6) and invalidity for a claim element, it will invalidate a claim under a lower standard than the law allows. Theoretically, a court could apply different standards of proof for each step, but that seems unlikely in practice where the inquiry essentially collapses into a single step.
Aside from the specification, courts also may consider the prosecution history and extrinsic evidence, such as technical dictionaries, when considering whether Section 112(6) applies to a claim element.25 This may be true especially with terms that appear to be means-substitute claim terms but convey a technical meaning for certain arts—a "nonce" word in one technical area may carry a specific meaning in another. To determine whether an alleged nonce word conveys to one of ordinary skill in the art structure for performing a claimed function that removes that nonce word from Section 112(6)'s requirements, courts likely will consider extrinsic evidence where that structure is not articulated in the intrinsic record.
An example is the word "module," which was at issue in Williamson. In the original, withdrawn panel decision, the majority used technical dictionaries to conclude that a "module" had "understood dictionary meanings as connoting either hardware or software structure to those skilled in the computer arts."26 While the later Williamson decision construed "module" as a nonce word, the original decision at least suggests that courts may consult extrinsic evidence to determine whether Section 112(6) applies to an alleged nonce, means- substitute claim term.
The fact that district courts may consider extrinsic evidence in determining whether an alleged nonce term has a structural meaning also implicates whether greater deference will be given to the district court in making such a determination. The Supreme Court's recent decision in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc.27 held that the Federal Circuit must review district court claim construction factual findings addressing extrinsic evidence under a clear error standard, as opposed to the de novo standard of review applied to district court findings concerning intrinsic evidence. In the context of Section 112(6), when a district court consults extrinsic evidence, such as technical dictionaries or expert testimony, to determine whether Section 112(6) applies to a claim term including an alleged nonce, means-substitute, that decision will be reviewed for clear error. But, if the district court determines whether Section 112(6) applies to a claim term based on the intrinsic evidence alone, the Federal Circuit will review the district court's finding using a de novo review standard.
The difference in review may result in providing patentees a strategy when their specifications are less descriptive. When the specification does not provide structural support for a functional claim term, a patentee's hope for avoiding Section 112(6) will rest on the district court's interpretation of extrinsic evidence. If the patentee convinces the district court that the extrinsic evidence shows that an alleged functional claim term actually connotes structure, the patentee has a standard-of-review advantage on appeal because the Federal Circuit will review the district court's decision for clear error. This, of course, presupposes that the patentee succeeds. If the patentee relies solely on the specification as evidence that the claim term connotes structure, the Federal Circuit will review the district court decision de novo on appeal.
The Williamson opinion explains that its holding was, in part, to reverse the "unwarranted," "uncertain," and "inappropriate" characterization of the Section 112(6) presumption articulated in Lighting World and Flo Healthcare.28 Most emphatically, however, Williamson's holding addresses "the proliferation of functional claiming untethered to § 112, para. 6 and free of the strictures set forth in the statute."29 While Williamson does not directly refer to software patents as the source of this "proliferation," the claims in Williamson concern a computer-implemented invention. Perhaps more telling, however, is Chief Judge Prost's dissent in Apple, Inc. v. Motorola, Inc., which predates Williamson and sets the stage for its holding.30
Apple concerned, among other things, construing claim terms related to its patent on the use of finger contacts to control a touchscreen. While the claim terms did not recite a "means for" performing a function, they followed a similar format: "a heuristic for determining . . . ."31 The district court concluded that Section 112(6) applied to the "heuristic" claim elements because they recited function without reciting sufficient structure performing the function. The district court did not invalidate the claims as indefinite because the specification contained sufficient structure corresponding to the claimed function.32 The Federal Circuit reversed the analysis but not the result, finding that Motorola failed to overcome the strong presumption in Lighting World that claim elements not reciting "means" do not invoke Section 112(6). Acknowledging that "there is some analytical overlap" between the two steps of the Section 112(6) invalidity analysis, the majority found that the specification disclosed sufficient structure related to the "heuristic" claim elements to avoid application of Section 112(6).
In dissent, Chief Judge Prost criticized the majority's decision because its analysis collapsed the two-step analysis of Section 112(6) into a single step which, in her view, "renders the category of non-indefinite means-plus-function claim terms a null set."33 She stated further that if Federal Circuit precedent dictates that the "heuristic" claim elements do not fall under Section 112(6), it is time to revisit when Section 112(6) applies to claim elements, "particularly for computer-implemented inventions."34 Seeing no difference between a claim reciting "a next item heuristic for determining . . . " and a "a next item means for determining . . . ," she argued that Apple's claims provide a "stark example" of broad functional claiming in software without being subject to the restraints of Section 112(6).35 She also cited, and agreed with, a law review article criticizing the Federal Circuit's failure to apply Section 112(6) to claims covering computer-implemented inventions, which was said to have resulted "in a plethora of software patents claimed not on the basis of the technology the patentee actually developed, but on the basis of the function that technology performs. . . . [U]nder this functional claiming rubric the software patents with the least actual technical content end up with the broadest claims . . . a function of its lack of technical specification."36
Chief Judge Prost's dissent in Apple set the stage for the policy behind the en banc portion of Williamson. The "proliferation of functional claiming" identified in Williamson refers to computer-implemented inventions, and Williamson's holding may be a reaction to the perception that functional claiming for computer-implemented inventions has become too prevalent. Similar to Apple, Williamson considered whether Section 112(6) applied to claim terms directed to a computer-implemented invention that did not recite "means." Although the cases had different outcomes, the court decided Apple using the rule of law that Williamson expressly overruled: the strong presumption that Section 112(6) does not apply to claim elements failing to recite "means." Williamson's en banc holding may have been a reaction to the outcome in Apple and the withdrawn panel decision in Williamson, which initially found the claims did not invoke Section 112(6).
The lesson here may be a warning for those drafting or litigating patents directed to computer-implemented inventions. Williamson is not only important for its rule of law, but also for the policy reasons driving that rule of law. It may signal that the Federal Circuit is more willing to apply Section 112(6) to what it sees as functional claims directed to computer-implemented inventions.
Williamson presents questions concerning when Section 112(6) applies, the standard of review attached to the "means" presumption, the deference afforded to district courts on appellate review, and the future of claims directed to computer-implemented inventions. Given that Williamson is only a few months old, those answers may take time. So far, there has been one Federal Circuit decision and a few district court decisions applying Williamson's holding to non-means claim terms, and the results are mixed.
Two examples show Williamson might lead to broader application of Section 112(6). First, in Media Rights Technologies, Inc. v. Capital One Financial Corp. et al.,37 the Federal Circuit affirmed a pre- Williamson decision that Section 112(6) applied to claim terms reciting a "compliance mechanism" without reciting structure. There, the patentee argued that the "compliance mechanism" was similar to the "modernizing device" claim term in Inventio AG v. ThyssenKrupp Elevator Ams. Corp.,38 which the Federal Circuit held did not fall under the Section 112(6). In affirming the district court's decision, the Federal Circuit distinguished the claims from those in Inventio which were supported by "extensive structural description in the specification."39 The Federal Circuit also noted that Inventio was decided under the pre-Williamson standard.40
In a second example from the District of Massachusetts, Voice Domain Technologies, LLC v. Apple Inc., Judge Hillman found that Section 112(6) applied to claim terms reciting a "coupling mechanism for providing [a] microphone signal," and a "microphone interpretation mechanism."41 Yet, some courts may not apply Section 112(6) as liberally. For example, in Smartflash LLC v. Apple Inc., Judge Gilstrap in the Eastern District of Texas found that Williamson's holding did not affect his decision that Section 112(6) did not apply to the claim terms "processor" and "code."42 While Smartflash arrived at a different result than Media Rights Technologies and Voice Domain Technologies, the three cases are similar in that the patents were directed to computer-implemented inventions. So, when the answers to the questions raised by Williamson come, they likely will come at the benefit (or expense) of patents directed to software and computer-implemented inventions.
Endnotes
1 Williamson v. Citrix Online, LLC, No. 13-1130 (Fed. Cir. June 16, 2015).
2 35 U.S.C. § 112, paragraph 6 (pre-AIA); 35 U.S.C. § 112(f) (post-AIA).
3 See Lighting World Inc. v. Birchwood Lighting, Inc., 382 F.3d 1354, 1358 (Fed. Cir. 2004).
4 Flo Healthcare Solutions, LLC v. Kappos, 697 F.3d 1367, 1374 (Fed. Cir. 2012).
5 Williamson, slip. op. at 16.
6 Id. at 4 (J. Newman dissent).
7 35 U.S.C. § 112, paragraph 6 (pre-AIA); 35 U.S.C. § 112(f) (post-AIA) (emphasis added).
8 See, e.g., Warner-Jenkinson Co., Inc. v. Hilton Davis Chemical Co., 520 U.S. 17, 28 (1997) ("Congress enacted § 112, ¶ 6, in response to Halliburton Oil Well Cementing Co. v. Walker").
9 Halliburton Oil Well Cementing Co. v. Walker, 329 U.S. 1 (1946).
10 Id. at 9, n. 7.
11 Id. at 11.
12 Williamson, slip op. at 8 (J. Reyna, concurring-in-part).
13 Personalized Media Communications, LLC v. Int'l Trade Comm'n, 161 F.3d 696, 703 (Fed. Cir. 1998) (citing Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d 1580, 1583 (Fed.Cir.1996)).
14 Williamson, slip op. at 14.
15Flo Healthcare at 1374.
16 Williamson, slip op. at 15.
17 Id. at 6 (J. Reyna, concurring-in-part).
18 See Microsoft Corp. v. i4i Ltd. P'ship, 131 S. Ct. 2238, 2442 (2011).
19 Williamson, slip op. at 6 (J. Reyna, concurring-in-part).
20 See Warner-Lambert Co. v. Teva Pharmaceuticals USA, 418 F.3d 1326, 1341 n.15 (Fed. Cir. 2005) ("A claim for patent infringement must be proven by a preponderance of the evidence, . . . which simply requires proving that infringement was more likely than not to have occurred."). Flo Healthcare at 1374.
21 Altiris, Inc. v. Symantec Corp., 318 F.3d 1363, 1375 (Fed. Cir. 2003).
22 Id.
23 See e.g., Inventio AG v. ThyssenKrupp Elevator Ams. Corp., 649 F.3d 1350, 1357 (Fed. Cir. 2011).
24 See Apple, Inc. v. Motorola, Inc., 757 F.3d 1286, 1335 (Fed. Cir. 2014) (J. Prost dissenting).
25 See Inventio at 1357.
26 See Williamson v. Citrix Online, LLC, 770 F.3d 1371, 1379 (Fed. Cir. 2014) (Williamson (withdrawn)).
27 Teva Pharms. USA, Inc. v. Sandoz, Inc., 574 U. S. ____ (2015).
28 Williamson, slip op. at 15.
29 Id.
30 Apple, 757 F.3d at 1334 (J. Prost dissenting).
31 Id. at 1295.
32 Id. at 1295-96.
33 Id. at 1135 (J. Prost dissenting).
34 Id.
35 Id. at 1137 (J. Prost dissenting).
36 Id. at 1137 (J. Prost dissenting) (citing Mark A. Lemley, "Software Patents and the Return of Functional Claiming," 2013 Wis. L.Rev. 905 (2013)).
37 Media Rights Techs, Inc. v. Capital One Fin. Corp. et al., No. 14-1218 (Fed. Cir. Sept. 4, 2015).
38 Inventio AG v. ThyssenKrupp Elevator Ams. Corp., 649 F.3d 1350, 1357 (Fed. Cir. 2011).
39 Media Rights Technologies, slip op. at 9.
40 Id. at 11.
41 See Voice Domain Technologies v. Apple Inc., Case No. 13-40138, (D. Mass Aug. 4, 2015) (Section 112(6) applies to claim terms reciting "mechanism").
42 See Smartflash LLC v. Apple Inc., Case No. 6:13-CV-447 (E.D. Tex. July 7, 2015).
Originally printed in Intellectual Property & Technology Law Journal. This article is for informational purposes, is not intended to constitute legal advice, and may be considered advertising under applicable state laws. This article is only the opinion of the authors and is not attributable to Finnegan, Henderson, Farabow, Garrett & Dunner, LLP, or the firm's clients.
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