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S&P updates MidCap 400 index

NEW YORK (AP) -- S&P Dow Jones Indices LLC announced Monday that Rosetta Resources Inc. will replace Catalyst Health Solutions Inc. in the S&P MidCap 400 index after the close of trading on July 5.

The move comes as a result of SXC Health Solutions Corp.'s acquisition of Catalyst Health Solutions, expected to be completed Monday night. Rosetta Resources, based in Houston, is an onshore oil and gas exploration and production company.

S&P Dow Jones Indices is a subsidiary of The McGraw-Hill Companies and operates a number of key stock market indices.