* CEO Rolet diversified LSE’s business
* Kept investment bank customers on side (Adds Rolet conference call, background on Rolet's history at the exchange)
By Noor Zainab Hussain and Huw Jones
LONDON, Oct 19 (Reuters) - Xavier Rolet, chief executive of the London Stock Exchange Group, will step down at the end of next year, just under a decade after he took charge and transformed the company with a string of deals.
Rolet has broadened the exchange's focus beyond share trading into derivatives and data through these acquisitions, including clearing house LCH and global indexes firm Russell.
Under his leadership, the LSE's market value has risen from less than 1 billion pounds to almost 14 billion pounds, helped by the diversification.
But his efforts to push through the exchange's third attempt to merge with Deutsche Boerse to create a global markets' behemoth ended in failure.
Rolet, who joined the group from Lehman Brothers, said last year that he would leave if a merger with Deutsche Boerse went through. But the collapse of that deal in March meant he opted to stay on for longer.
"At times we took risks, we made a few moves, sometimes they could be qualified as bold moves in order to broaden the spectrum of our products, achieve global relevance," Rolet told an analyst call on the LSE's third-quarter results, published on Thursday.
The Frenchman, at the helm of what had been a quintessentially English club in the City of London for much of its 300-year history, said he was "completely committed" to ensuring a smooth transition to a new CEO by the time he leaves in December 2018.
One critical area remains what Rolet called an "inherited weakness" - the lack of a major futures trading footprint, leaving it trailing rivals CME, ICE and Deutsche Boerse in this area.
But Rolet is seen as being shrewd in making sure his main customers, the big investment banks, are always listened to. When the LSE took over cross-border trading platform Turquoise and later on LCH, the investment banks remained shareholders.
Rolet, a former investment banker himself, ensured that the banks had a large minority stake in LCH and a say in its running, a model that led to strong growth in volumes and one that rival Deutsche Boerse is now trying to mimic.
"Overall his legacy is one of many good deals which entirely transformed LSE as a group, albeit with the concern that he never really integrated any of his purchases adequately," exchanges expert Patrick Young said.
Rolet took over at LSE from Clara Furse in May 2009, ending a prolonged period of fending off takeover attempts and questions about the exchange's future.
His banking background made him a popular choice among the exchange's largest customers.
LSE said in a separate statement on Thursday that group income for the quarter ended Sept rose 17 percent to 1.66 billion pounds ($2.19 billion), with revenue up 14 percent to 486 million pounds as its clearing and FTSE Russell businesses grew strongly.
Thirteen analysts had forecast total income of 477.5 million pounds, according to consensus estimates provided by the company. ($1 = 0.7569 pounds)
Reporting by Noor Zainab Hussain in Bengaluru; Editing by Rachel Armstrong and Jane Merriman