Dec 13 - Standard & Poor's Ratings Services said today that it assigned its 'BBB-' issue-level rating to The Williams Cos. Inc.'s proposed $850 million senior unsecured notes. The company intends to use net proceeds from the notes to fund a portion of its $2.4 million investment in Access Midstream Partners L.P. (BB-/Stable/--). As of Sept. 30, 2012, Williams had total consolidated debt of about $9.5 billion. Tulsa-based Williams is a diversified energy company that operates interstate gas pipelines, natural gas liquids transportation pipelines, and gathering and processing assets. Williams also owns about 70% of master limited partnership Williams Partners L.P. (BBB/Stable/--). For 2013, we forecast that Williams will achieve a consolidated total debt to EBITDA ratio of about 4.4x. (For the corporate credit rating rationale, see our research update on Williams published Dec. 12, 2012 on RatingsDirect.) RELATED CRITERIA AND RESEARCH Key Credit Factors: Criteria For Rating The Global Midstream Energy Industry, April 18, 2012 The Williams Cos. Inc. Corporate credit rating BBB/Stable/-- New Rating $850 mil senior unsecured notes BBB- Complete ratings information is available to subscribers of RatingsDirect on the Global Credit Portal at www.globalcreditportal.com. All ratings affected by this rating action can be found on Standard & Poor's public Web site at www.standardandpoors.com. Use the Ratings search box located in the left column.