US REIT Act of 2012

Update and Streamline REIT Act of 2012 or US REIT Act of 2012 - Amends the Internal Revenue Code, with respect to the tax treatment of real estate investment trusts (REITs), to: (1) modify safe harbor rules for avoiding penalties for prohibited sales of rental and timber properties by REITs by allowing three-year averaging of sales proceeds for such properties, (2) repeal the preferential dividend rule for dividend payments to shareholders of publicly-offered REITs, (3) revise REIT income and assets tests to allow treatment of publicly-offered REIT debt instruments and personal property leased or mortgaged in connection with REIT real property as real estate assets, (4) make permanent the treatment of gain from sales of timber property and mineral royalties as qualifying REIT income, and (5) revise the calculation of REIT earnings and profits to avoid duplicate taxation of REIT shareholders.