Court Issues Mixed Claim Construction Ruling in Ethanol Processing Patent Case

A previous post reported on the consolidation of a number of patent infringement suits brought by GreenShift and its New York subsidiary, GS Cleantech, against a host of ethanol producers across the midwestern United States.

GreenShift has accused the defendants of infringing U.S. Patent No. 7,601,858 (‘858 Patent), entitled “Method of processing ethanol byproducts and related subsystems.”

The ‘858 Patent is directed to methods of recovering oil from byproducts of ethanol production using the process of dry milling, which creates a waste stream comprised of byproducts called whole stillage.

According to the ‘858 Patent, whole stillage contains valuable oil but prior processes for recovering this oil have been expensive or inefficient.

GreenShift’s patented method includes mechanically separating the whole stillage into distillers wet grains and thin stillage and then running the thin stillage into an evaporator to form a concentrated byproduct, or syrup.  The syrup is fed through a second centrifuge, which separates usable corn oil from the syrup.

In September 2010 the Judicial Panel on Multidistrict Litigation granted GreenShift’s motion to consolidate the 11 actions in the Southern District of Indiana.

Recently, the court issued a “Markman” decision (GS-Markman-Order), a claim construction order that provides the court’s interpretations of key disputed terms of the patent claims.

There were several terms of the ‘858 Patent claims at issue, the most important of which were  “concentrated byproduct”, “concentrate”, “thin stillage concentrate” and “concentrated thin stillage” (collectively construed by the court as “the Concentrate Terms”), as well as “mechanically processing”.

In one instance, the court adopted the defendants’ narrower proposed construction.  In the other, it went with GreenShift’s broader proposed definition.

The question in interpreting the Concentrate Terms was essentially what the byproduct or concentrated substance is.  GreenShift argued that it is any product consisting of water, oil and solids, while the defendants contended it should be limited to a syrup.

The court agreed with the defendants and construed the Concentrate Terms to mean “syrup containing water, oil, and solids resulting from the concentrating or evaporating process.” 

According to the court, this interpretation “naturally aligns” the claim language with the description in the ‘858 Patent, which uses the terms “concentrate” and “syrup” interchangeably to identify the composition described by the Concentrate Terms.

The court construed the term “mechanically processing” to mean “to subject to a mechanical device (or devices) to effect a particular result.”  Despite defendants’ contention that the term means “processing with a centrifuge,” the court agreed with GreenShift that the plain meaning of the term requires a broader construction.

As discussed before in this space, the claim construction phase of patent litigation is extemely important, often leading to settlement or dismissal on summary judgment.

With what appears to be a mixed ruling leaving no clear winner, it will be interesting to see what happens next in this major biofuels litigation.

Eric Lane Avatar

Eric Lane

Eric Lane, the founder and principal of Green Patent Law, is an intellectual property lawyer and registered U.S. patent attorney in New York and is a member of the bar in New York and California. Eric has more than two decades of experience working with wind, solar PV, CSP, biofuels, and geothermal, energy storage technologies, carbon capture and sequestration, medical devices, data communications, mechanical, chemical, internet and software.