En Banc Federal Circuit Abandons 'Strong' Presumption That A Limitation Is Not Subject To 35 U.S.C. § 112, Paragraph 6

On June 16, 2015, the Federal Circuit revisited its prior precedent regarding when a claim limitation is subject to 35 U.S.C. § 112, paragraph 6. In Williamson v. Citrix Online, LLC, No. 13-1130 ("Citrix"),1 the en banc court held that the absence of the word "means" gives rise only to a rebuttable presumption—not a "strong" presumption—that Section 112, paragraph 6 does not apply to the limitation.

BACKGROUND OF SECTION 112, PARAGRAPH 6

Section 112, paragraph 62 allows a patentee to recite a claim limitation as a "means or step for performing a specified function," but "without the recital of structure, material, or acts in support thereof." Claim limitations drafted in this format, known as "means-plus-function" limitations, are "construed to cover the corresponding structure, materials, or acts described in the specification and equivalents thereof."3 If the specification fails to disclose sufficient structure for performing the corresponding function of a means-plus-function limitation, the claim is invalid as indefinite under 35 U.S.C. § 112, paragraph 2.4

Under prior Federal Circuit precedent, the absence of the term "means" gave rise to a "strong" presumption that Section 112, paragraph 6 does not apply.5 Overcoming this presumption required a "showing that the limitation essentially [was] devoid of anything that [could] be construed as structure."6

THE ORIGINAL PANEL DECISION

Citrix involved U.S. Patent No. 6,155,840, which concerns a method and system for conducting distributed learning over a computer network. Asserted claim 8 of the '840 patent recites the following "distributed learning control module" limitation:

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.

In a November 5, 2014 decision, a three-judge Federal Circuit panel held that this limitation was not subject to Section 112, paragraph 6.7 Relying on its prior precedent and reversing the district court, the panel reasoned that appellees had failed to rebut the "strong" presumption that the "module" limitation was not a means-plus-function limitation, due to its absence of the word "means."8

THE EN BANC CITRIX DECISION

On June 16, 2015, the Federal Circuit withdrew its prior opinion and issued a new decision in the case. In the en banc...