Since "Micropolis" is licensed under the GPL, users can do anything they want with it that conforms with the GPLthe only restriction is that they cannot call it "SimCity" (along with a few other limitations to protect EA's trademarks). This allows other, differently named projects to be forked from the Micropolis source code. Improvements to the open source code base that merits EA's approval may be incorporated into the official "OLPC SimCity" source code, to be distributed with the OLPC under the trademarked name "OLPC SimCity", but only after it has been reviewed and approved by EA.