Roger J. Bergfeld, Sr. Denise I. Bergfeld v. Unimin Corporation, Martin Marietta Corporation, Also Known as Lockheed Martin Corporation

WOLLMAN, Circuit Judge.

Roger and Denise Bergfeld appeal the district court’s 1 adverse grant of summary judgment on their products liability claim. The district court concluded that Roger Bergfeld’s (Bergfeld) employer, the John Deere Dubuque Works Foundry, was a sophisticated user of the silica sand that allegedly caused his injuries and thus that Martin Marietta Corporation 2 (Lockheed Martin) had no duty to warn Deere of the risks posed by excessive exposure to silica sand. We affirm.

I

From 1976 to 1983 Lockheed Martin sold silica sand to Deere for use in making molds and cores in Deere’s…