Ropes & Gray Wins Federal Circuit Victory for Sioux Steel Company

Following oral argument, the Federal Circuit issued a Rule 36 affirmance on June 15 in Prairie Land Millwright Services, Inc. v. Sioux Steel Co.  On behalf of Sioux Steel Company, Ropes & Gray successfully defended the Patent Trial and Appeal Board’s decision on the validity of the ‘937 patent, which claims a pivot unit structure in a paddle sweep, used to empty grain bins.  

Prairie Land asserted that the PTAB had erred in its construction of the claim “carry,” including because the claim was construed more narrowly than the construction offered by Sioux Steel in the ongoing district court case Sioux Steel Co. v. Prairie Land Millwright Servs., Inc., in the Northern District of Illinois. Sioux Steel explained that regardless of the Boards construction of “carry”, the Board correctly found that Prairie Land failed to offer sufficient proof of invalidity.  

The Ropes team included appellate & Supreme Court partner Douglas Hallward-Driemeier and IP litigation associate Kathryn Thornton.