United States: The Federal Circuit Alters The Means-Plus-Function Analysis

The Federal Circuit's recent en banc opinion in Williamson v. Citrix Online, LLC, 2015 U.S. App. LEXIS 10082, *2 (Fed. Cir. June 16, 2015) (Williamson II) may result in courts finding that more claims include "means-plus-function" claim elements, which could significantly affect the scope and validity of those claims.  As a result of Williamson II, the Federal Circuit has weakened the "presumption" that claim elements lacking the term "means" fall outside the means-plus-function analysis.

1. "Means-Plus-Function" Claim Elements

Means-plus-function claim elements are specifically authorized by the Patent Act, which provides that "[a]n 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." 35 U.S.C. § 112(f) (previously 35 U.S.C. § 112, ¶ 6, prior to the America Invents Act).  The Patent Act also provides that a means-plus-function element "shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof."

For example, rather than claiming a nail or a screw as part of an invention, a patentee could instead simply claim a "means for fastening," which would be limited to the corresponding fasteners disclosed in the specification (perhaps, for example, nails, screws, staples, and glue) and equivalents thereof.  But without a corresponding structure, material, or acts for performing the claimed function, the claim will be invalid for indefiniteness under 35 U.S.C. § 112(b).

Thus, a determination that a claim includes a means-plus-function element may greatly impact both the scope of the claim, and how its validity may be challenged.  Importantly, however, this determination is not based solely on the presence or absence of the word "means" in the claim.

2. Prior Legal Standard for Claim Elements Without the Term "Means": The "Strong Presumption"

Before the Federal Circuit's decision in Williamson  II, a claim element that actually used the term "means" created a rebuttable presumption that § 112, ¶ 6 applied, and a claim element that did not use the term "means" created a strong rebuttable presumption ("not readily overcome") that § 112, ¶ 6 did not apply.  Lighting World, Inc. v. Birchwood Lighting, Inc., 382 F.3d 1354, 1358 (Fed. Cir. 2004).  In the absence of the word "means," this strong presumption that § 112, ¶ 6 did not apply could be overcome by proving that the claim element failed to recite a "sufficiently definite structure[.]"  Id.; see also Apple Inc. v. Motorola, Inc., 757 F.3d 1286, 1296-97 (Fed. Cir. 2014).

In determining whether there was a "sufficiently definite structure," courts were not limited to the claim language itself, but were also permitted to interpret the claims in light of the written description supporting them, the prosecution history, plus any relevant extrinsic evidence (such as technical dictionaries).  Inventio AG v. Thyssenkrupp Elevator Ams. Corp., 649 F.3d 1350, 1356-57 (Fed. Cir. 2011).  The question often came down to whether those skilled in the art would conclude that the claim element was so devoid of anything that could be construed as structure that the drafter constructively engaged in means-plus-function claiming.  See id. at 1357; Flo Healthcare Solutions, LLC v. Kappos, 697 F.3d 1367, 1374 (Fed. Cir. 2012).

For example, in Lighting World, the Federal Circuit held that the claim element of "connector assembly for connecting..." (which lacked the term "means") recited sufficiently definite structure as evidenced by the intrinsic record and dictionary definitions, and therefore the accused infringers did not successfully rebut the strong presumption that § 112, ¶ 6 did not apply.  382 F.3d at 1359-63.  Similarly, in Inventio, the Federal Circuit held that the claim elements of "modernizing device...for converting...[,]" and "computing unit for reading..." (both without the term "means") recited sufficiently definite structures in light of the claims and written descriptions, and therefore § 112, ¶ 6 did not apply to either.  649 F.3d at 1354, 1357-60.  Applying the same "strong presumption" in Flo, the Federal Circuit held that the claim element of "height adjustment mechanism for altering..." (without "means") imparted a sufficiently definite structure as shown by the surrounding claim language, dictionary definitions, and written description, and therefore § 112, ¶ 6 did not apply.  697 F.3d at 1372, 1374-75.  And as recently as last year in Apple v. Motorola, the Federal Circuit held that the claim element of "heuristic for determining..." (which lacked the term "means") recited sufficiently definite structure as evidenced by the claims and specification, and therefore the strong presumption was once again not overcome.  757 F.3d at 1295, 1300-04.

3. The Shift from "Strong Presumption" to a Mere "Presumption"

The Federal Circuit recently overturned this long line of cases in Williamson II, holding that the heightened "strong" presumption was "unwarranted."  When the Federal Circuit first addressed this issue six months ago in Williamson v. Citrix Online, LLC, 770 F.3d 1371 (Fed. Cir. 2014) ("Williamson I"), it continued to apply the 'strong' presumption established in its earlier precedent, holding that the claim element of "distributed learning control module for receiving... relaying... and... coordinating ..." recited sufficiently definite structure as evidenced by the surrounding claim language, the specification, and dictionary definitions, bringing it outside the ambit of § 112, ¶ 6.  Williamson I, 770 F.3d at 1375, 1377-80.  As a result, the Federal Circuit vacated the district court's determination that claims-at-issue were invalid as indefinite under 35 U.S.C. § 112, ¶ 2, based on its erroneous construction that § 112, ¶ 6 applied.  Id. at 1380.

But the Federal Circuit reversed course just six months later when, sitting en banc in Williamson II, it held that "[o]ur opinions in Lighting World, Inventio, Flo Healthcare and Apple have thus established a heightened bar to overcoming the presumption that a limitation expressed in functional language without using the word 'means' is not subject to § 112, para. 6."  2015 U.S. App. LEXIS 10082 at *17-18.  The court found that the heightened bar of the "strong" presumption was "unwarranted, is uncertain in meaning and application, and has the inappropriate practical effect of placing a thumb on what should otherwise be a balanced analytical scale."  Id. at *18.  Instead, the Federal Circuit stated that it would overrule the characterization of the presumption as "strong," and proceed with applying the presumption as it had done prior to Lighting WorldId.  The en banc court also expressly overruled "the strict requirement of 'a showing that the limitation essentially is devoid of anything that can be construed as structure.'"  Id. 

The en banc court in Williamson II articulated the new standard as follows: "The standard is 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...the presumption can be overcome and § 112, para. 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.'"  Id. at *18-19 (internal citations omitted).

Under this new standard, the Federal Circuit determined that the claims-at-issue in the Williamson cases were invalid for indefiniteness.  Id. at *30.  First, where the Federal Circuit had previously held that the strong presumption of Williamson I was not overcome, it now determined that less-heightened presumption of Williamson II was overcome, holding that the claim element "distributed learning control module for receiving... relaying... and... coordinating ..." failed to recite a sufficiently definite structure to bring it out of the ambit of § 112, ¶ 6.  Id. at *19-24.  Accordingly, the Federal Circuit treated the element as a "means-plus-function" one, despite the absence of the word "means."  Id.

Second, because the element was a "means-plus-function" one, the Federal Circuit then analyzed whether the specification disclosed a "corresponding structure" to the claimed functions of "receiving... relaying... and... coordinating...[,]" and concluded that it did not  Id. at *25-30.   As a result, the Federal Circuit agreed with the district court's initial decision that the challenged claims were invalid as indefinite under 35 U.S.C. § 112, ¶ 2.  Id. at *30.

4. Conclusion

As the different results in the two Williamson decisions illustrate, this new standard could result in more claims being found to be "means-plus-function" claims, which in turn could give rise to previously unavailable claim construction and indefiniteness defenses.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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