Oilfield-services company Smith International Inc. is asking a federal judge in Delaware to lift a stay on its patent infringement suit against rival Baker Hughes Inc., arguing that Baker Hughes was taking advantage of long delays for inter partes review in the case.

On Tuesday, Smith’s attorneys asked U.S. District Judge Eduardo C. Robreno to allow the case to resume, after the U.S. Court of Appeals for the Federal Circuit last week ruled that the bulk of the asserted claims on two Baker Hughes’ patents for oil and gas drilling equipment were patentable and subject to a court challenge.