What are the essential differences between the BSD and MIT licences? 1
Are the Eclipse Public License (EPL) and the General Public License (GPL) compatible? 2
Unless a Secondary License has been specified in the EPL-2.0, the EPL and the GPL are not compatible in any combination where the result would be considered either: (a) a derivative work (which Eclipse interprets consistent with the definition of that term in the U.S. Copyright Act ) or (b) a work based on the GPL code, as that phrase is used in the GPLv2, GPLv3 or the GPL FAQ as applicable. Further, you may not combine EPL and GPL code in any scenario where source code under those licenses are both the same source code module.
Based upon the position of the Free Software Foundation, you may not combine EPL and GPL code in any scenario where linking exists between code made available under those licenses. The above applies to both GPL version 2 and GPL version 3.
Or simplier 3:
In terms of GPL compatibility, the Eclipse Public License version 2.0 is essentially equivalent to version 1.0. The only change is that it explicitly offers the option of designating the GNU GPL version 2 or later as a “secondary license” for a certain piece of code.
If an initial contributor releases a specific piece of code and designates GNU GPL version 2 or later as a secondary license, that provides explicit compatibility with those GPL versions for that code. (Doing so is roughly equivalent, for users, to releasing that piece of code under a dual license, EPL | GPL.) However, the EPL2 without this designation remains incompatible with the GPL.
Links to start digging into the problem: