An activist investor has ramped up the pressure on the London Stock Exchange Group (LSEG), calling for an extraordinary meeting to oust its chairman over claims he pushed out chief executive Xavier Rolet.
Christopher Hohn, investment manager of The Children's Investment Fund Management (TCI), has written to chairman Donald Brydon, accusing him of offering poor explanations for Mr Rolet's departure and claiming that confidentiality agreements were barring full disclosure of his plans.
"You have failed to provide shareholders with any substantive basis for the removal of the chief executive," Mr Hohn said.
"Hiding behind confidentiality agreements denies shareholders the ability to view your actions and demonstrates the bad corporate governance over which you are presiding."
TCI - which owns more than 5% of LSEG - is now calling for an extraordinary shareholder meeting, where it intends to put forward a motion that would remove Mr Brydon and retain Mr Rolet as chief executive.
Mr Hohn said in the letter that he was accepting an invitation by the LSEG to meet with its board next week.
The London Stock Exchange Group declined to comment.
The LSEG last month announced Mr Rolet would be standing down in 2018 after nearly a decade at the helm, during which time its stock market value has soared from £800 million to nearly £14 billion.
In an earlier letter to Mr Brydon from November 3, Mr Hohn argued Mr Rolet had created "enormous value" through acquisitions and "excellent operational management".
The fund had been urging Mr Brydon to resign on his own terms, for Mr Rolet's contract to be extended and for the group to suspend the search for his successor - warning it would otherwise trigger the extraordinary meeting.
Mr Rolet's tenure has seen the LSE seal a string of acquisitions, although it was marred by the recent failed attempt at a £21 billion merger with German rival Deutsche Borse to create a European trading powerhouse after it was blocked by the European Commission in March.
This marked the third doomed attempt at a tie-up between the two companies after previous setbacks in 2000 and 2005.
Before the LSE Group, Mr Rolet held a number of senior posts at failed investment bank Lehman Brothers, most recently as chief executive of its French operation.
He also previously held senior positions at Dresdner Kleinwort Benson, Credit Suisse First Boston and Goldman Sachs.
The London Stock Exchange responded to TCI's initial letter on November 3, saying it had followed a "proper governance process to plan an orderly succession for the CEO".
"The FCA was kept informed throughout the process and emphasised the importance of the plan for an orderly succession.
"Xavier Rolet will be providing input into the process to identify his successor and is focussed on his role as CEO until his successor is appointed," the LSEG added.