Activist investor Carl Icahn has successfully forced AmTrust’s CEO, his in-laws and their backers to increase by 9.3 percent their bid to take the company private.

In an announcement issued before markets open in New York, AmTrust said that Barry Zyskind, his wife’s family - the Karfunkels - and Stone Point had agreed to increase the offer price to $14.75 per share, valuing the firm at around $2.95bn.

The revised offer follows a dramatic few weeks for AmTrust, which postponed a shareholder vote after Icahn shocked markets revealing that he had taken a 9.4 percent stake in the company to block the proposed $13.50 per share offer.

The activist investor disclosed that he had bought up just under a quarter of the shares in AmTrust that are not owned by Zyskind and his in-laws in a scathing open letter criticising the deal and sparking weeks of public sparring between Icahn and the US insurer.

But now AmTrust has revealed that it has reached a deal with the activist investor who has agreed to back the revised terms.

“We are pleased that we were able to work with George Karfunkel and Barry Zyskind to reach a settlement that is in the best interest of all stockholders,” Icahn said in a statement.

“By raising the merger price to $14.75, over $100mn of incremental value has been created for public stockholders,” the billionaire investor continued.

“Most importantly, we want to thank all the stockholders whose vital support was so critical to achieving this outcome.”

AmTrust also revealed that a shareholder vote on the deal, which has been postponed until 21 June, will be independently audited after Icahn raised concerns about controls in place for the ballot, which was originally scheduled for 4 June.

“The amended agreement follows significant engagement with our public stockholders, and is consistent with our commitment to maximise value for public stockholders,” said Don DeCarlo who heads the special committee put together by AmTrust to assess the deal.

“We continue to believe that the immediate, certain, premium value provided in this agreement is in the best interest of AmTrust’s public stockholders and look forward to the completion of the transaction,” he went on.