From the GPLv3 Discussion Draft 1:

Therse are some of my highlites
Some countries have adopted laws prohibiting software that enables users
to escape from Digital Restrictions Management. DRM is fundamentally
incompatible with the purpose of the GPL, which is to protect users'
freedom; therefore, the GPL ensures that the software it covers will
neither be subject to, nor subject other works to, digital restrictions
from which escape is forbidden.

Finally, every program is threatened constantly by software patents. We
wish to avoid the special danger that redistributors of a free program will
individually obtain patent licenses, in effect making the program
proprietary. To prevent this, the GPL makes it clear that any patent must
be licensed for everyone's free use or not licensed at all.
And in legalese..
2. Basic Permissions.


This License gives unlimited permission to privately modify and run the
Program, provided you do not bring suit for patent infringement against
anyone for making, using or distributing their own works based on the

3. Digital Restrictions Management.

As a free software license, this License intrinsically disfavors
technical attempts to restrict users' freedom to copy, modify, and share
copyrighted works. Each of its provisions shall be interpreted in light of
this specific declaration of the licensor's intent. Regardless of any
other provision of this License, no permission is given to distribute
covered works that illegally invade users' privacy, nor for modes of
distribution that deny users that run covered works the full exercise of
the legal rights granted by this License.

No covered work constitutes part of an effective technological protection
measure: that is to say, distribution of a covered work as part of a system
to generate or access certain data constitutes general permission at least
for development, distribution and use, under this License, of other
software capable of accessing the same data.

7. License Compatibility.


Aside from additional permissions, your terms may add limited kinds of
additional requirements on your added parts, as follows:


e) They may impose software patent retaliation, which means permission
for use of your added parts terminates or may be terminated, wholly or
partially, under stated conditions, for users closely related to any
party that has filed a software patent lawsuit (i.e., a lawsuit
alleging that some software infringes a patent). The conditions must
limit retaliation to a subset of these two cases: 1. Lawsuits that lack
the justification of retaliating against other software patent lawsuits
that lack such justification. 2. Lawsuits that target part of this
work, or other code that was elsewhere released together with the parts
you added, the whole being under the terms used here for those parts.

11. Licensing of Patents.

When you distribute a covered work, you grant a patent license to
the recipient, and to anyone that receives any version of the work,
permitting, for any and all versions of the covered work, all
activities allowed or contemplated by this License, such as
installing, running and distributing versions of the work, and using
their output. This patent license is nonexclusive, royalty-free and
worldwide, and covers all patent claims you control or have the right
to sublicense, at the time you distribute the covered work or in the
future, that would be infringed or violated by the covered work or any
reasonably contemplated use of the covered work.
Also if anyone knows a beter forum for this then " Product / Book / Training / Conference Reviews " sugest..