| Additional IP Rights Grant (Patents) | |
| "This implementation" means the copyrightable works distributed by | |
| Google as part of the Dart Project. | |
| 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, transfer, and otherwise run, modify and propagate the contents | |
| of this implementation of Dart, 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 | |
| this implementation of Dart. This grant does not include claims that | |
| would be infringed only as a consequence of further modification of | |
| this implementation. 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 this implementation of Dart or any code | |
| incorporated within this implementation of Dart constitutes direct or | |
| contributory patent infringement, or inducement of patent | |
| infringement, then any patent rights granted to you under this License | |
| for this implementation of Dart shall terminate as of the date such | |
| litigation is filed. |