Takeaway: Petitioner failed to meet its burden of showing obviousness where its reason for combining references was based on assumptions about the references that were not fully supported by the references.

In its Final Written Decision, the Board held that Petitioner had not met its burden to prove, by a preponderance of the evidence, that claims 1-12 of the ’497 patent are unpatentable. The ’497 patent relates to dispensing liquid “from a bulk container by empirically determining the liquid surface height and opening a dispensing valve for a time period that is calculated using a value of liquid specified to be dispensed and the empirically-determined liquid surface height.”

The Board began its analysis with claim construction. The Board adopted Petitioner’s proposed constructions of various claim terms in its Decision to Institute and Patent Owner did not dispute them. Thus, the Board maintained those constructions. Patent Owner requested construction of three other terms in its Preliminary Response. The Board did not adopt Patent Owner’s proposals in its Decision to Institute, because it was not persuaded that they represented the broadest reasonable interpretation of those terms. The Board further determined that, for purposes of its Final Written Decision, it is unnecessary for it to construe those terms anyway.

The Board analyzed Patent Owner’s Motion to Exclude the Militzer Declaration (Petitioner’s expert). Patent Owner argued that Dr. Militzer does not meet the definition of a person of ordinary skill in the art, and thus is not qualified “to conduct an obviousness analysis as one of ordinary skill in the art at this matter.” The Board explained that “[t]o testify as an expert under FRE 702, a person need not be a person of ordinary skill in the art, but rather “‘qualified in the pertinent art.’” The Board determined that although Dr. Militzer has never worked as an engineer in the field of liquid dispensing equipment, he has been a professor since 1998 specializing in thermo-fluid fields, such as thermodynamics, heat transfer, and fluid dynamics, and, as part of his teaching, he has “developed a series of laboratory experiments to demonstrate fundamental concepts and measure relevant flow characteristics. Thus, the Board agreed with Petitioner that Dr. Militzer is qualified to testify and that his testimony would assist the Board in understanding the mechanics and dynamics in the prior art.

The Board then evaluated the obviousness grounds of unpatentability. Petitioner’s obviousness challenges to each of the independent claims contended that: (1) Pascoe discloses all of the method steps except “evaluating a polynomial” to determine valve open time; (2) Wang discloses that a polynomial equation can be used to predetermine valve open time based on the amount of liquid in the container to achieve accurate dispensing of liquid from a container; and (3) one of ordinary skill in the art would have been motivated to use a polynomial equation as taught by Wang to predetermine valve open time in Pascoe to achieve improved accuracy. Patent Owner argued that Petitioner had failed to meet its burden because: (1) Pascoe does not predetermine valve open time; (2) Wang does not disclose a polynomial with coefficients correlated to volume; and (3) Petitioner’s motivation to combine Pascoe and Wang is based on improper hindsight reasoning. The Board was persuaded by Patent Owner’s third argument.

Patent Owner specifically argued that “the problem addressed in Wang is poor dispensing accuracy associated with liquid level sensors,” while Pascoe’s device utilizes a load cell rather than a level sensor, and thus Pascoe’s method is not subject to the inaccuracies with which Wang was concerned. Accordingly, Patent Owner contended that one of ordinary skill in the art would not have understood from Wang that a method of using a polynomial equation to calculate a liquid dispense time would provide improved accuracy over a method dispensing liquids that relies on direct and continuous measurement of weight using a load cell, as done in Pascoe’s method. Additionally, Patent Owner argued the one of ordinary skill in the art could not have been motivated to use a polynomial equation to determine valve open time in Pascoe, “because Pascoe’s method has the advantage that it can be used with containers of varying cross section, and Wang’s polynomial equation is only viable when used with a container of constant cross section.”

The Board noted that “Petitioner’s contention that one of ordinary skill in the art would have been motivated to a polynomial equation to predetermine valve open time in Pascoe’s method relies on Dr. Militzer’s testimony that adapting Wang’s polynomial equation for use in Pascoe would have involved nothing more than simple calculations.” Dr. Militzer further testified that one of ordinary skill in the art would have known how to adapt Wang’s polynomial equation to use a variable obtained from Pascoe’s load cell in place of the variable obtained from Wang’s level sensors based on an understanding that: “(1) fluid velocity determines the time it takes to dispense a given amount of liquid through a nozzle at the base of a container; (2) fluid velocity is dependent on pressure at the nozzle; and (3) in a container of uniform cross-sectional area, pressure is directly related to height, and weight is the pressure multiplied by the cross-sectional area.” Patent Owner pointed out that Dr. Militzer’s testimony is based on the assumption that Pascoe uses a container of constant cross section. The Board agreed that the evidence supports Patent Owner’s contention that Pascoe uses containers of varying shapes, and in which cross section varies during dispensing of a liquid, such as an aseptic bag. The Board determined that Petitioner had failed to provide persuasive evidence that one of ordinary skill in the art reasonably would have expected that use of a polynomial equation to predetermine valve open time for dispensing a user-specified volume of liquid from a container of varying cross section, would provide greater dispensing accuracy than Pascoe’s method of continuously monitoring weight in the container and closing the valve when a desired volume has been reached. Accordingly, the Board concluded that Petitioner had not shown, by a preponderance of the evidence, that one of ordinary skill in the art would have had a reason to modify Pascoe’s method to predetermine valve open time using a polynomial equation as taught by Wang.

A.C. Dispensing Equipment Inc. v. Prince Castle LLC, IPR2014-00511
Paper 33: Final Written Decision
Dated: August 4, 2015
Patent: 8,534,497 B2
Before: Linda M. Gaudette, Donna, M. Praiss, and Mitchell G. Weatherly
Written by: Gaudette