154Chapter 10 Appendixcontributor version.In the following three paragraphs, a "patent license" is anyexpress agreement or commitment, however denominated,not to enforce a patent (such as an express permissionto practice a patent or covenant not to sue for patentinfringement). To "grant" such a patent license to a partymeans to make such an agreement or commitment not toenforce a patent against the party.If you convey a covered work, knowingly relying on apatent license, and the Corresponding Source of the workis not available for anyone to copy, free of charge andunder the terms of this License, through a publicly availablenetwork server or other readily accessible means, then youmust either (1) cause the Corresponding Source to be soavailable, or (2) arrange to deprive yourself of the benefit ofthe patent license for this particular work, or (3) arrange, ina 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 workin a country, or your recipient's use of the covered work in acountry, would infringe one or more identifiable patents inthat country that you have reason to believe are valid.If, pursuant to or in connection with a single transaction orarrangement, you convey, or propagate by procuringconveyance of, a covered work, and grant a patentlicense to some of the parties receiving the covered workauthorizing them to use, propagate, modify or convey aspecific copy of the covered work, then the patent licenseyou grant is automatically extended to all recipients of thecovered work and works based on it.A patent license is "discriminatory" if it does not includewithin the scope of its coverage, prohibits the exercise of,or is conditioned on the non-exercise of one or more ofthe rights that are specifically granted under this License.You may not convey a covered work if you are a party toan arrangement with a third party that is in the businessof distributing software, under which you make paymentto the third party based on the extent of your activity ofconveying the work, and under which the third party grants,to any of the parties who would receive the covered workfrom you, a discriminatory patent license (a) in connectionwith copies of the covered work conveyed by you (orcopies made from those copies), or (b) primarily for andin connection with specific products or compilations thatcontain the covered work, unless you entered into thatarrangement, or that patent license was granted, prior to 28March 2007.Nothing in this License shall be construed as excludingor limiting any implied license or other defenses toinfringement that may otherwise be available to you underapplicable patent law.12. No Surrender of Others' Freedom.If conditions are imposed on you (whether by court order,agreement or otherwise) that contradict the conditions ofthis License, they do not excuse you from the conditions ofthis License. If you cannot convey a covered work so as tosatisfy simultaneously your obligations under this Licenseand any other pertinent obligations, then as a consequenceyou may not convey it at all. For example, if you agreeto terms that obligate you to collect a royalty for furtherconveying from those to whom you convey the Program,the only way you could satisfy both those terms and thisLicense would be to refrain entirely from conveying theProgram.13. Use with the GNU Affero General PublicLicense.Notwithstanding any other provision of this License, youhave permission to link or combine any covered workwith a work licensed under version 3 of the GNU AfferoGeneral Public License into a single combined work, andto convey the resulting work. The terms of this License willcontinue to apply to the part which is the covered work,but the special requirements of the GNU Affero GeneralPublic License, section 13, concerning interaction through anetwork will apply to the combination as such.14. Revised Versions of this License.The Free Software Foundation may publish revised and/or new versions of the GNU General Public License fromtime to time. Such new versions will be similar in spirit tothe present version, but may differ in detail to address newproblems or concerns.Each version is given a distinguishing version number. IftheProgram specifies that a certain numbered version of theGNU General Public License "or any later version" appliesto it, you have the option of following the terms andconditions either of that numbered version or of any laterversion published by the Free Software Foundation. If theProgram does not specify a version number of the GNUGeneral Public License, you may choose any version everpublished by the Free Software Foundation.If the Program specifies that a proxy can decide whichfutureversions of the GNU General Public License can beused, that proxy's public statement of acceptance of aversion permanently authorizes you to choose that versionfor the Program.Later license versions may give you additional or differentpermissions. However, no additional obligations areimposed on any author or copyright holder as a result of