Futures exchange operator CME Group (CME) said Monday that Craig Donohue, its chief executive since 2004, will step down at the end of the year.

 In a press release, the CME Group said Terrence Duffy, who is currently executive chairman, will step into an expanded role as executive chairman and president. Current President Phupinder Gill will take over as chief executive officer.

"After 23 years at CME Group, including eight years as CEO, this is a bittersweet decision for me but I am ready to explore new challenges," Donohue said in a statement. 

The CME’s board has extended Duffy’s and Gill’s contracts as part of their expanded roles, the company said. The exchange’s existing management team will remain in place.

“Under Craig's guidance, CME Group has grown into the preeminent global derivatives exchange company,” Duffy said in the statement. 

CME’s shares were lower in after hours trading after falling $6.36, or 2.3%, to $270.20.

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