Federal Circuit No. 2013-1130

The en banc Federal Circuit in Williamson v. Citrix online, LLC overruled prior precedent that accorded a strong presumption that 35 U.S.C. § 112, para. 6 does not apply to claims lacking the term "means" and upheld the district court's finding that "distributed learning module" is a 'means-plus-function' limitation.

Means-plus-function claiming occurs when a claim term is drafted in a manner that invokes § 112, para. 6 (now § 112(f)). To determine whether § 112, para. 6 applies to a claim limitation, precedent has long recognized the importance of the presence or absence of the word “means.”  The use of the word “means” in a claim element creates a rebuttable presumption that § 112, para. 6 applies and the failure to use the word “means” also creates a converse presumption that § 112, para. 6 does not apply.  In particular, the presumption flowing from the absence of the term ‘means’ was considered a strong one that is not readily overcome.  To overcome this strong presumption, the challenger has to show that the limitation essentially is devoid of anything that can be construed as structure. 

Williamson argued that the district court erred in construing the term “distributed learning control module” as being governed by 35 U.S.C. § 112, para. 6 in that the district court failed to give appropriate weight to the “strong” presumption against means-plus-function claiming that attaches to claim terms that do not recite the word “means.” 

Overruling the characterization of such a presumption as 'strong', the Federal Circuit held that when a claim term lacks the word “means,” 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,” citing Watts v. XL Sys., Inc. (Fed. Cir. 2000) 

Applying this standard, the court found that the limitation at issue is subject to § 112, para. 6 after observing that “module” is a well-known nonce word that can operate as a substitute for “means” in the context of § 112, para. 6.  Further, the court noted that the prefix “distributed learning control” does not impart structure into the term “module.” The court acknowledged Williamson's argument that the presence of modifiers can change the meaning of “module,” But nevertheless found that the presence of “distributed learning control” did not provide any structural significance to the “module” at issue.   

Further, with the observation that the specification fails to disclose any structure, i.e., an algorithm, corresponding to the “coordinating” function