According to the articles of the MPL, programs licensed under the MPL can adopt the multi-licenses model:

a. The initial developer of a program can specify different licenses for different specific part of code. The licensees can pick up among the designated licenses one license that suits the part of code they are using. One of the representative projects that adopt the MPL is Mozilla, which in turns adopts a triple license model that lists MPL, GPL and LGPL as available options. The documentation in the program will make it clear which licenses are used for the different parts of the program. The licensee may also contact the initial developers. According to this multi-license module, if any contributor modifies the program licensed under the MPL, the following conditions may apply:

i. If the modification is not subject to the terms of other licenses, the modification will still be subject to the MPL or the license terms specified by the initial developer.
ii. If the modification is already subject to the terms of another license, a written consent from the initial developer is all that is needed for the modification to be subject to the original licensing terms.

b. In addition, the licensees can adopt a license different from the MPL when they redistribute the executable binary form of the program, so long as the chosen license does not conflict with the MPL and so long as the recipient of the executable binary is well informed that the source code and the received binary adopt different licensee terms and the executable form is provided by the licensee in question, whose action has nothing whatsoever to do with the initial developer.