Cliffs Natural Resources Inc.'s leading competitive position as the largest iron ore pellet supplier in the U.S. may result in improved operating performance as steel industry conditions improve for integrated steel producers. The Cleveland-based company is going to market with a proposed $350 million senior unsecured notes issue due 2020. We assigned our 'BBB-' corporate credit rating to the company and rated its proposed senior unsecured notes 'BBB-'. The outlook is stable. On March 10, 2010, Standard&Poor's Ratings Services assigned its 'BBB-' corporate credit rating to Cliffs Natural Resources Inc. The outlook is stable. At the same time, we assigned an issue-level rating of 'BBB-' to Cliffs' proposed $350 million senior unsecured notes due 2020, based on preliminary