Google hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer implementations of the WebM Specifications, where such license applies only to those patent claims, both currently owned by Google and acquired in the future, licensable by Google that are necessarily infringed by implementation of the WebM Specifications. If You or your agent or exclusive licensee institute or order or agree to the institution of patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that any implementation of the WebM Specifications constitutes direct or contributory patent infringement, or inducement of patent infringement, then any rights granted to You under the License for the WebM Specifications shall terminate as of the date such litigation is filed. "WebM Specifications" means the specifications to the WebM codecs as embodied in the source code to the WebM codecs or any written description of such specifications, in either case as distributed by Google.
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