(Adds detail on succession process)
May 12 (Reuters) - Nasdaq OMX Group Inc said on Monday it had hired back Adena Friedman as a co-president, a move that according to Friedman's former boss puts her in a lead position to run the company.
The transatlantic exchange operator has been working for months to figure out who will succeed its chief executive, Robert Greifeld. Friedman, who left Nasdaq in 2011 to become chief financial officer of private equity firm Carlyle Group LP, is one of the candidates on the list, Reuters reported last year.
The urgency of succession planning first hit the board when Friedman left. Greifeld had been positioning Friedman as his successor, and her departure put a spotlight on the lack of depth in the management bench that remained.
Since then, Nasdaq has endured multiple calamities that have raised further questions among investors about the company's succession plan. Last August, trading on all Nasdaq stocks was halted for three hours due to a glitch in a data processing system run by the exchange operator.
In 2012, Nasdaq botched Facebook Inc's market debut, eventually agreeing to pay up to $41.6 million to firms harmed in the IPO and a $10 million fine to regulators.
Insiders have told Reuters that Greifeld, who is in his mid-50s, has no immediate plans to retire. He signed a five-year contract in 2012.
Nasdaq said on Monday that Friedman will be president of global corporate, information, and technology solutions. The company also named Hans-Ole Jochumsen, currently an executive vice president, as president of global trading and market services.
Carlyle's co-founder co-CEO David Rubenstein said in a statement, "We are sad to see Adena go but understand this is a once-in-a-lifetime opportunity for her to serve as their president and to be the leading candidate to some day run Nasdaq."
Eric Noll, previously seen as the top internal candidate to replace Greifeld, left Nasdaq OMX Group in November to become president and chief executive of brokerage ConvergEx. [ID: nL2N0JA1BL]
Carlyle chief accounting officer Curt Buser, a former Ernst & Young LLP audit partner, will replace Friedman on an interim basis until her successor is named, Carlyle said. (Reporting by Ankush Sharma in Bangalore and Greg Roumeliotis and Dan Wilchins in New York; editing by Sofina Mirza-Reid and Andrew Hay)