If the First Closing occurs, except for the right of Purchaser to indemnification under Section 16.2 , Purchaser shall be deemed to have waived, to the fullest extent permitted under Law, any right to contribution against any Indemnified Seller Party (including any contribution under CERCLA or any other Environmental Law) and any and all other Claims and rights it may have against or from any Indemnified Seller Party arising under or based on any Law or other legal theory (whether in contract, tort, equity, or otherwise).