At foss.my 2009, Brian Aker asked Richard Stallman at his keynote, about the Oracle/Sun acquisition (with a focus on MySQL), with regards to the parallel licensing approach used by MySQL. Brian was referring to:
As only the original rights holder can sell commercial licenses, no new forked version of the code will have the ability to practice the parallel licensing approach, and will not easily generate the resources to support continued development of the MySQL platform.
from Richard’s Letter to the EC opposing Oracle’s acquisition of MySQL. Listen to the discussion between Brian and Richard.