Standard Clauses addressing licensee challenges to the licensed patent's validity or enforceability or assertions that the licensee's activities are outside the license scope or otherwise would not infringe the licensed patent without the license. These Standard Clauses include a sample patent challenge definition and different licensor remedies for patent challenges, including termination of the patent license agreement and increased licensee payment obligations. These Standard Clauses have integrated notes with important explanations and drafting and negotiating tips.