Comment 3 for bug 52953

> The Ubuntu policy is clear and not clear at same time.

From http://www.ubuntu.com/ubuntu/licensing

Documentation, Firmware, and Drivers

Ubuntu contains licensed and copyrighted works that are not application
software. For example, the default Ubuntu installation includes
documentation, images, sounds, video clips and firmware. The Ubuntu
community will make decisions on the inclusion of these works on a
case-by-case basis, ensuring that these works do not restrict our
ability to make Ubuntu available free of charge, and that Ubuntu remains
redistributable by you.