: Chesapeake Energy to join S&P MidCap 400

Chesapeake Energy Corp. CHK will replace Mercury Systems Inc. MRCY on the S&P MidCap 400, S&P Dow Jones Indices said on Wednesday, while Mercury Systems will replace Arconic Corp. ARNC in the S&P SmallCap 600. Both moves take hold prior to the start of trading on Aug. 21. “Apollo Global Management Inc. APO is acquiring Arconic in a deal that is expected to close soon, pending final closing conditions. Mercury Systems is more representative of the small-cap market space,” S&P Dow Jones Indices said. Last week, S&P Dow Jones Indices said Kenvue Inc., KVUE maker of Tylenol and Benadryl, would join the S&P 500 Index SPX. Shares of Chesapeake were up 5.5% after hours on Wednesday.

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