INCOME TAXES

6 Months Ended

Jun. 30, 2012

INCOME TAXES

15.

INCOME TAXES: The increase in the effective tax rate for the second quarter of 2012 as compared to the second quarter of 2011 is due to the tax impact of the Duferdofin-Nucor impairment charge being fully recorded in the second quarter of 2012. Nucor has concluded U.S. federal income tax matters for years through 2006. The years 2004 and 2007 are open to the extent net operating losses were carried back. The 2008 to 2011 tax years are open to examination by the Internal Revenue Service. In 2011 the Canada Revenue Agency completed an audit examination for the periods 2006 to 2008 for Harris Steel Group Inc. and subsidiaries with immaterial adjustments to the income tax returns. The tax years 2008 through 2011 remain open to examination by other major taxing jurisdictions to which Nucor is subject (primarily Canada and other state and local jurisdictions).