S&P will make the following changes to the S&P 500, S&P MidCap 400 and S&P SmallCap 600 indices.

Alpha Natural Resources Inc. (NYSE: ANR) will replace Massey Energy Corp. (NYSE: MEE) in the S&P 500 index after the close of trading on Wednesday, June 1. Alpha Natural Resources is acquiring Massey Energy in a deal expected to be completed on or about that date pending final approvals.

S&P SmallCap 600 constituent Triumph Group Inc. (NYSE: TGI) will replace Pride International Inc. (NYSE: PDE) in the S&P MidCap 400 index and Inter Parfums Inc. (NASD: IPAR) will replace Triumph Group in the S&P SmallCap 600 index after the close of trading on Tuesday, May 31. Ensco plc (NYSE: ESV) is acquiring Pride International in a deal expected to be completed on or about that date pending final approvals.

Standard & Poor's will monitor these transactions, and post any relevant updates on its website: www.standardandpoors.com.

Alpha Natural Resources engages in the production, processing, and sale of coal. Headquartered in Abingdon, VA, the company will be added to the S&P 500 GICS (Global Industry Classification Standard) Coal & Consumable Fuels Sub-Industry index.

Triumph Group engages in the design, engineering, manufacture, repair, overhaul, and distribution of aircraft components. Headquartered in Wayne, PA, the company will be added to the S&P MidCap 400 GICS Aerospace & Defense Sub-Industry index.

Inter Parfums engages in the manufacture, marketing, and distribution of various fragrances and fragrance related products. Headquartered in New York, NY, the company will be added to the S&P SmallCap 600 GICS Personal Products Sub-Industry index.

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