National Recovery Technologies, Inc. v. Magnetic Separation Systems, Inc.

National Recovery Technologies, Inc. (NRT) (plaintiff) owned a patent (the ‘576 patent) directed to a process for separating containers made of polyvinyl chloride (PVC) from containers made of polyester (PET). Such separation is desirable in a recycling operation, because PVC and PET have different chemical characteristics. Yet that separation is difficult to attain manually, because PVC and PET containers look similar. Prior systems addressed this problem by irradiating containers one at a time with X-rays, taking advantage of the fact that the differing chemical properties between PVC and PET meant that they exhibited different X-ray transmittance characteristics. Generally, PET containers exhibit higher transmittance readings than PVC containers. One drawback of such prior systems noted in the ‘576 patent was that by the time many containers reach an X-ray station, they were mangled in ways that resulted in irregular shapes, causing the containers to have significantly varying thicknesses. The thickness variations posed a problem, because at larger thicknesses, a PET container had lower transmittance readings that could resemble PVC transmittance readings, causing misclassification during the recycling operation. To deal with this problem, the ‘576 patent discussed taking readings from only regular portions of each container. Claim 1 of the ‘576 patent recited a process step of “(d) selecting for processing those of said process signals which do not pass through irregularities in the bodies of said material items . . . .” In the United States District Court for the Middle District of Tennessee, NRT sued Magnetic Separation Systems, Inc. and an individual (collectively, MSS) (defendants) for infringement of the ‘576 patent. MSS moved for summary judgment of invalidity of claim 1 for failure to satisfy the enablement requirement of 35 U.S.C. § 112. The district court found that the ‘576 patent specification failed to disclose how to select signals for processing based on whether they passed through container irregularities. Additionally, one of the inventors, Dr. Sommers, testified that as of NRT’s patent-application filing, additional research, development, and experimentation was needed to practice the invention recited in claim 1. The district court therefore granted MSS’s motion and extended the invalidity ruling to dependent claims 2–8 and 10. NRT appealed.