Sir Ken Morrison, the former chairman of UK supermarket chain Morrisons, may face an investigation from the country's shares watchdog, for allegedly failing to disclose the transfer of millions of pounds worth of shares.

Under Financial Services Authority rules, a significant shareholder in a business must notify the company of all share sales within two days of the transaction happening. Additionally, the company must then make the disclosure public no later than the following day.

According to a statement to the stock exchange yesterday (1 March), Morrisons said it was notified yesterday of four changes to Sir Ken's shareholding in the company between 16 September 2009 and 21 June 2010. He has gradually reduced his voting rights in the company from 6.07% to just under 0.9%.

The retailer said that it understood that the changes in voting rights have arisen as a result of Sir Ken retiring as one of the trustees of certain family trusts and other estate and tax planning exercises he undertook following his retirement as a director of the company.

Morrisons said that, based on an analysis by the company's brokers, it estimates that members of the wider Morrison family continue to own approximately 9% of the company's issued share capital.

The FSA said it is unable to confirm or deny whether it has launched an investigation into Sir Ken, now Morrisons' life president, citing confidentiality agreements.