definiens: means that a Third Party acquires, by merger, sale of assets or otherwise, ( i ) all or substantially all of the equity of a Party, ( ii ) all or substantially all of the assets or business of a Party to which the subject matter of this Agreement relates or ( iii ) after the Research Term, all or substantially all of the assets or business of a Party with respect to a Draft Pick Target exclusively licensed to such Party ( any such Third Party with respect to clauses ( i ) through ( iii ), an ) . On written notice to Constellation, Licensee may assign this Agreement, in its entirety, or, after the end of the Research Term, on a Draft Pick Target -by - Draft Pick Target basis, to the relevant Acquirer in connection with an M&A Event or to an Affiliate . Following the later of ( a ) the expiration or termination of the Research Term or ( b ) the Option Termination Date ( as defined 73 CONFIDENTIAL EXECUTION VERSION under the Option Agreement ) or termination of the Option Agreement ( unless, in each case, the Option ( as defined therein ) has been exercised thereunder in which case Constellation may not assign this Agreement unless and until the Merger Agreement is termi nated pursuant to Section 13.1 thereof ), Constellation may assign this Agreement, in its entirety or on a Draft Pick Target -by - Draft Pick Target basis, on written notice to Licensee, ( y ) to an Affiliate ; or ( z ) to the relevant Acquirer in connection with a n M&A Event . Notwithstanding any provisions of this Agreement to the contrary, if this Agreement is assigned by a Party in connection with an M&A Event, such assignment and/or the occurrence of such M&A Event ( whether or not a formal assignment of this Agr eement occurs ) shall not provide the other Party with rights or access to any intellectual property or technology of the relevant Acquirer . Except as expressly provided in this Section 15.3, neither Party may assign any of its rights or delegate any of its obligations under this Agreement without the prior written consent of the other Party, such consent not to be unreasonably withheld . Subject to the foregoing, this Agreement will inure to the benefit of and bind the Parties ’ successors and assigns . Any as signment in contravention of the foregoing shall be null and void