German billionaire Erich Kellerhals, co-founder of electronics retail giant Media Markt and a major shareholder in its current owner Ceconomy CECG.DE>, has died at the age of 78, a spokesman for his holding company Convergenta said on Thursday.

Kellerhals founded Media Markt with two business partners in 1979. Media-Saturn now has more than 1,000 stores in 15 European countries and is majority-owned by consumer electronics group Ceconomy, which split from Metro this year.

“He was a remarkable entrepreneurial figure to whom we all owe much gratitude,” Media-Saturn’s management said.

Kellerhals, who held a stake of just over 21 percent in Media-Saturn, had for years been at odds with Ceconomy over the management of the business, most notably its move into the fast-growing online market as well as the split from Metro.

German magazine Der Spiegel reported this month that representatives of Kellerhals’s holding company Convergenta had refused to approve Media-Saturn’s annual accounts.

Ceconomy shares rose almost 4 percent to a record high in early Thursday trading. A Frankfurt-based trader said this reflected hopes that Kellerhals’s heirs would be able to reach an agreement with the company’s management.

Ceconomy said in a statement: “We send our sympathy and condolences to his family.”

 
Kellerhals died on Dec. 25 surrounded by family, the Convergenta spokesman said. He leaves behind his wife and business partner of over 50 years, Helga, and a son.

According to Forbes, Kellerhals was worth about $2 billion.