FRANKFURT (Reuters) - Deutsche Boerse's DB1Gn.DE Chief Executive Carsten Kengeter, who is under investigation for insider trading, frequently met and spoke by telephone with his London Stock Exchange counterpart in the months before they announced official merger talks, Der Spiegel magazine reported on Friday.

FILE PHOTO: Carsten Kengeter, CEO of Deutsche Boerse in Frankfurt, Germany March 1, 2017. REUTERS/Ralph Orlowski/File Photo

Frankfurt’s public prosecutor has been investigating Kengeter for possible insider trading for the purchase in December 2015 of 4.5 million euros ($5.3 mln) in Deutsche Boerse shares, two months before the two exchange operators announced merger negotiations.

Kengeter has denied all allegations of wrongdoing, saying the shares he purchased were part of an official Deutsche Boerse compensation plan. “Insider trading goes against everything I stand for,” he told shareholders in May.

Der Spiegel said that Kengeter and LSE LSE.L CEO Xavier Rolet met or telephoned almost weekly in the second half of 2015, from the moment that Kengeter assumed the helm of Deutsche Boerse in June 2015.

A report from German market watchdog BaFin shows that between June 2015 and January 2016 Rolet’s calendar showed the two had 15 conversations, while Deutsche Boerse disclosed four appointments between the two, Der Spiegel said.

The BaFin report of the 15 meetings came from information it received from the British market watchdog, which had access to Rolet’s calendar, according to Der Spiegel.

Representatives for BaFin and its British counterpart FCA declined to comment.

A spokesman for Deutsche Boerse said, “From the beginning of the investigation, we said we were cooperating with the authorities.”

A spokesman for LSE declined to comment immediately.

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