Speechly Bircham is facing a claim worth more than £4m from Betfair founder Mark Davies and his wife Miranda for alleged negligence and/or breach of retainer for advice the firm gave them when they tried to sell their shares in the company.

In a claim lodged in the Queen's Bench division of the High Court last month (16 August), the couple, who are trustees of the Giselle Davies Family Trust and the Davies Family Trust, which both hold stakes in online gambling company Betfair, argue that that the losses caused by Speechly's advice stands at around £4.48m.

According to the writ, the couple instructed Speechly private client partner Charles Hutton that they wanted to sell their shares when Betfair went public in October last year, with the intention of selling when shares reached at least £13 each.

When the company listed on 22 October, shares were trading at £15.50, at which point Davies was told that selling was not possible because the shares had not been registered properly.

With share prices continuing to fall, the Trusts have not sold the shares, with the price per share standing at £6.08 at the time the claim was issued.

The form states: "Neither trust has sold the Betfair shares given the loss that each would thereby sustain. Insofar as may be necessary the claimants will say that the defendant is liable for the totality of the losses sustained because the defendant's breach of retainer/negligence placed the trusts in a position where they were unable to sell at the price that was available."

The pair are claiming damages and interest. Carter-Ruck litigation lawyer Rebecca Toman is advising the Davies on the claim. Mark Davies resigned from Betfair in July 2010.