June 16, 2006 — United States Steel Corp. reported that each of its outstanding shares of 7.00% Series B Mandatory Convertible Preferred Shares ("MEDS") has automatically converted into 3.1928 shares of United States Steel Corp. common stock pursuant to the terms of the MEDS.

The conversion will increase the company's shares of common stock outstanding by approximately 16 million shares.

All shares of MEDS are held in book entry form by the Depository Trust Company (DTC). Delivery of common shares and the mechanics of conversion will be handled by DTC in accordance with its rules. Beneficial owners of the MEDS should contact their broker or dealer for additional information concerning the conversion.