Mårten Mickos

Dual licensing. Mickos, a Finnish executive, ran MySQL AB from 2001 to its sale to Sun Microsystems in 2008, growing it on a dual-licence model: the database was free under the GPL for anyone who shared their own code, while companies embedding it in closed products bought a commercial licence. The code itself was largely written by Michael Widenius and the founding team. Sun paid about a billion dollars.