Duhn Oil Tool, Inc. v. Cooper Cameron Corp.

Duhn Oil Tool, Inc. filed a complaint for patent infringement against firm client Cooper Cameron Corp. over certain oil field equipment. The case was initially tried to a jury in the U.S. District Court for the Eastern District of California. After a three-week trial, the jury found infringement, but also determined that all the asserted claims were invalid as obvious and/or anticipated. The court granted a JMOL in favor of Duhn Oil on Cameron’s defense of obviousness and ordered a new trial on anticipation. At the second trial, which was to the bench, the court found that all the asserted claims were anticipated by the prior art, with the exception of one dependent claim that the jury in the first trial had found to be obvious. Upon Cameron’s motion, the court set aside the earlier JMOL and re-instated the jury’s finding that the remaining claim was obvious. The court then entered judgment in favor of Cameron, invalidating all the asserted claims and ordering the Duhn Oil take nothing. Duhn Oil has filed a notice of appeal.