"2) when the Software is distributed as source code, the licensee is prohibited to change the license of the Software to any “viral” copyleft-type license, such

"2) when the Software is distributed as source code, the licensee is prohibited to change the license of the Software to any “viral” copyleft-type license, such as, inter alia: GPL, LGPL, EPL, MPL, etc." This is what happens when you don't talk to lawyers, I guess. Combining MIT and GPL doesn't relicense anything, they're mutually compatible - you can fulfil both license obligations simultaneously. So actually, it doesn't appear to be an issue using EMIT-licensed software within GPLed software, so long as you retain the EMIT license on the original code and any subsequent modifications.