Bank Sarasin & Co, the Swiss private banking group, today denied that it has secretly bought shares on behalf of a client, responding to an article carried in the German journal Focus that had implied such behaviour.

The bank said that as recently as 22 July, it had notified German regulatory authorities and Douglas Holding, the German retail chain, that it owns 10.8 per cent of the latter firm as part of its own shareholdings.

“This notification was published both by the German financial services regulator and Douglas Holding on their respective websites. Bank Sarasin’s purchase of the shares in question in Douglas Holding was therefore neither done secretly nor on behalf of Mr Müller or any other third party,” Sarasin said in statement.

The news story highlights how there is an increasing focus on the extent to which banks and other institutions – such as hedge funds – disclose the investments that they make.