Parts of MEPIS products may incorporate GPL licensed binary code. If asked to do so, anyone causing the redistribution of GPLed binary code, is required to also redistribute the source code.
Read the announcement at MEPIS.org
On June 20, 2006, MEPIS received the following official opinion from the Free Software Foundation:
Any and all Linux distros/builds disseminated via the Internet are required to mirror the source code for all GPLed binary code they incorporate, even if they would otherwise never have possession of that source code. They do not have a safe harbor because they use the packages of well established distro X as the basis of their distro. Every redistribution is expected to comply with this position, or it will be considered to be in violation of the GPL, which will always be enforced whenever such a violation is brought to the FSF's attention. “Nobody gets a free pass.”
Thanks to my friends at DebCentral for the scoop