You may not impose any further restrictions on the exercise of the rights granted or affirmed under this
License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights
granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in
a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or
importing the Program or any portion of it.
11. Patents.
A "contributor" is a copyright holder who authorizes use under this License of the Program or a work on
which the Program is based. The work thus licensed is called the contributor's "contributor version".
A contributor's "essential patent claims" are all patent claims owned or controlled by the contributor,
whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by
this License, of making, using, or selling its contributor version, but do not include claims that would be
infringed only as a consequence of further modification of the contributor version. For purposes of this
definition, "control" includes the right to grant patent sublicenses in a manner consistent with the
requirements of this License.
Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under
the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run,
modify and propagate the contents of its contributor version.
In the following three paragraphs, a "patent license" is any express agreement or commitment, however
denominated, not to enforce a patent (such as an express permission to practice a patent or covenant
not to sue for patent infringement). To "grant" such a patent license to a party means to make such an
agreement or commitment not to enforce a patent against the party.
If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of
the work is not available for anyone to copy, free of charge and under the terms of this License, through
a publicly available network server or other readily accessible means, then you must either (1) cause the
Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent
license for this particular work, or (3) arrange, in a manner consistent with the requirements of this
License, to extend the patent license to downstream recipients. "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the covered work in a country, or your
64