Opera Software's founder and top owner Jon von Tetzchner is leaving the company, but will hold on to his stake of about 12.3 percent, he told Reuters on Monday.

I'm probably more ambitious and would like to move faster in all areas than the board and the current management do, he said. I have no plans to sell or reduce my Opera stake.

Jon von Tetzchner was Opera's chief executive from its creation in 1995 until 2010.