PTAB Overturns Rejection For Overlapping Ranges

• Published date: 15 November 2022
• Subject Matter: Intellectual Property, Food, Drugs, Healthcare, Life Sciences, Patent, Biotechnology & Nanotechnology
• Law Firm: Oblon, McClelland, Maier & Neustadt, L.L.P
• Author: Derek Lightner

On October 19, 2022, the Patent Trial and Appeal Board (PTAB) overturned the obviousness rejection of a claim to an aqueous dispersion. Claim 1 of the application in question, USSN 16/083,182 (the 182 Application), recited

[a]n aqueous dispersion comprising

(a) 5% to 40% of a continuous phase, by weight based on the weight of the aqueous dispersion, wherein the continuous phase comprises 75% to 100% water, by weight based on the weight of the continuous phase, and

(b) 60% to 95% of a distributed phase, by weight based on the weight of the aqueous dispersion, wherein the distributed phase comprises, by weight based on the weight of the distributed phase,

(i) 2% to 20% ethylcellulose polymer,

(ii) 70% to 97% food oil,

(iii) 1 % to 10% dispersant,

wherein the distributed phase comprises dispersed particles that are solid at room temperature.

The obviousness rejection of the above claim over the combination of WO 1992/003937 A2 (Zaks) and WO 2015/031244 A1 (Rogers) was appealed in the 182 Application.

The 182 Application was filed with four claims. The sole independent claim recited the above features, except for the final clause, and was first rejected as obvious over the combination of Zaks and a different secondary reference.In response, the applicant added the final clause to claim 1 and argued that the art failed to describe or make obvious (1) solid particles dispersed in a continuous aqueous medium; (2) changing Zaks's "oil-continuous emulsion having two liquid phases (liquid oil and water phases)" to "an aqueous dispersion having one solid phase and one liquid phase," with water being the continuous phase as claimed; and (3) changing Zaks's water-soluble aqueous gelling agents to being water-insoluble ethyl cellulose as claimed.

The examiner then finally rejected the claim over the combination of Zaks and Rogers, relying on Rogers for a dispersant being a fatty acid and for the use of ethylcellulose.The examiner relied merely upon Zaks's overlapping ranges of the oil and water phases ("the emulsions generally contain from about 30 to 80% by weight of the oil phase, and about 20 to 70% by weight of the aqueous phase") to argue that the specific continuous and distributed phases claimed would have been obvious, although Zaks described a continuous oil phase.The final rejection did not elaborate on a technical rationale for modifying this feature in Zaks, and merely relied upon the fact that the art taught mixing the oil and water phases.

The portion of...