In a surprise move, Bernhard Scheuble has stepped down as chairman and chief executive of German chemical and pharmaceutical company Merck KGaA after 24 years at the company. He will be replaced by board member Michael Roemer.

The suddenness of the announcement seemed to worry investors, and Goldman Sachs promptly downgraded Merck from ‘outperform’ to ‘inline’, saying it suggests there was disagreement with the majority shareholder, the Merck family, which owns 73% of the group. Shares in the company were down to 69.75 euros in mid-morning trading, from a close of 73 euros yesterday.

Prof Scheuble has held the positions of chairman and chief executive of Merck since 2000, having formerly served as head of the pharmaceuticals business at the company, a function he retained as CEO. This business will now be headed by Elmar Schnee.

No reasons were given for his abrupt departure, with Merck saying only that the 52-year-old ‘is resigning with mutual agreement and with immediate effect’.

Dr Roemer is another long-serving Merck executive, with 27 years under his belt, and in addition to donning the CEO mantle will maintain his current responsibilities for production, engineering, corporate purchasing, environmental issues and logistics, said Merck.

Merck posted a sizeable 57% increase in third quarter net income to 182 million euros in the third quarter of this year, while sales rose 9% to 1.47 billion euros.