Deutsche Börse is trying to prevent Werner Seifert, its ousted chief executive, from publishing a planned book about his experiences at the hands of rebel shareholders early this year.

Directors are using a dispute about the size of Mr Seifert's pay-off as a lever to block publication of the book which, they feel, could embarrass the stock exchange group and undermine attempts to rebuild investor relations.

"He's being difficult," said a person close to the board. "It would damage the Börse if he published a book now. He can do it in two or three years, fine. But we're not going to let him do it now."

Mr Seifert was ousted in May after pressure from investors, led by London-based hedge fund TCI. That followed a six-month battle during which Mr Seifert was forced to withdraw his plan for a takeover of the London Stock Exchange and agree to return €1.5 billion to investors.

Shareholders were told that forcing Mr Seifert's removal would cost the company about €10 million. Mr Seifert had more than a year of his contract to run and, if ousted, he was entitled to three times his pay for the rest of that period. But as the membership of the supervisory board has changed, so has the willingness to honour that contract unquestioningly.

In particular, lawyers are understood to be in dispute over the valuation of Mr Seifert's share options. The Börse is understood to be proposing a pay-out of about €8 million, while Mr Seifert is said to be asking for nearly €11 million. Mr Seifert declined to comment yesterday.

The search for Mr Seifert's replacement, meanwhile, is close to completion. A short-list of three or four, including candidates from abroad, is being debated.

The final choice for the new chief executive is expected to be announced in about a month's time.