PTAB Reverses Obviousness Rejections for Failure to Adequately Explain the Motivation to Combine References and that the Claimed Product Would Result from the Combination 

By Pat Halloran | November 23, 2022

The Applicant appealed the Examiner’s rejection of its claims to “[a]n aqueous dispersion comprising….a continuous phase” of “75% to 100% water” and “60% to 95% of a distributed phase” including “2% to 20% ethylcellulose polymer”, “70 to 97% food oil” and “1% to 10% dispersant, wherein the distributed phase comprises dispersed particles that are solid at room temperature” (RT).  Focusing on claim 1 in this review, the Examiner rejected the claim as being obvious over a reference (“Zaks”) disclosing emulsions containing an aqueous phase and an oil phase, with aqueous-soluble cellulose derivatives being in the aqueous phase.  The Examiner acknowledged Zaks did not disclose an oil phase comprising dispersed particles that are solid at RT but alleged that a secondary reference (“Rogers”) filled that gap.


The Applicant argued that Rogers did not teach an aqueous dispersion containing oil and did not therefore support the rejection.  The Examiner’s Answer argued that “Zaks and Rogers disclose the oil phase and aqueous phase are mixed together to form an aqueous emulsion” and “[t]he order of mixing the ingredients is prima facie obvious”, citing MPEP 2144.04.  The Applicant then argued that the Examiner was incorrect that “it would have been obvious to use the ethylcellulose polymers as the cellulose derivatives in the emulsion of Zaks” because “it is well known that ethylcellulose polymer is not water-soluble, and Zaks clearly indicated its cellulose derivatives are water-soluble.”


The Board disagreed with the Examiner’s analysis because:  1)  “Zaks indicates that the gelling agents used in its aqueous phase are water soluble”, “[t]here is no dispute that ethylcellulose is not water soluble”, and that finding this irrelevant because the “oil and water phase are ultimately mixed with each other” was erroneous; 2) the result of using “ethylcellulose as Zaks’ cellulose derivative” would result in ethylcellulose being “in Zaks’ aqueous phase, while claim 1 requires ethylcellulose in the oil phase” and “the Examiner has not shown that the same product would result”; and, 3) “the claims require the continuous phase to be the water phase”, “[t]here is no dispute that, in Zaks, the continuous phase is the oil phase”, and “the Examiner has not adequately explained why such would fall within the scope of claim 1”.  The Board, therefore, reversed the Examiner’s obviousness rejection.  This decision emphasizes that obviousness rejections, especially claims including multiple phases within a composition, must include a properly reasoned explanation of why one of ordinary skill in the art would have modified a prior art composition and that the same product as claimed would result.