Delta-X Corp. v. Baker Hughes Production Tools Inc.

Delta-X Corporation (plaintiff) was assigned United States Patent No. 4,286,925 (the 925 patent), which disclosed a means for turning off power to a well if the oil pump was experiencing fluid pound. Delta-X sued Baker Hughes Production Tools, Inc., and Baker CAC (collectively, Baker) (defendants) for infringement in federal court, arguing that Baker’s rod pump controllers infringed the 925 patent. Delta-X and Baker disagreed about the meaning of the term electrical comparator in the 925 patent. Baker requested that the district court instruct the trial jury that an electrical comparator was not synonymous with a computer. The district court declined to issue Baker’s requested instruction and instead chose to give the jury the task of claim interpretation. During jury instructions, the district court told the jury to compare the accused Baker device with the properly interpreted claims. Some parts of the jury instructions implied that the court would interpret the claims instead of the jury. However, the instructions also included multiple direct references to the jury’s responsibility to interpret the claims and then apply the law to their interpretations. Baker objected to the issued jury instructions at the end of trial but did not move for a directed verdict. The jury found that Baker was liable for willful infringement of the 925 patent under the doctrine of equivalents. Delta-X requested enhanced damages, attorney’s fees, and costs based on the willfulness finding. Baker requested that the district court deny Delta-X’s motion and moved for judgment notwithstanding the verdict (JNOV) on the jury’s willfulness finding. The district court denied Delta-X’s request for enhanced damages, granted Baker’s motion for JNOV, and set aside the jury’s finding of willfulness. The district court also found independently of the JNOV that Delta-X had failed to make a sufficient case for enhanced damages. Delta-X appealed, and Baker cross-appealed.