Any notices, requests, demands and other communications provided for by this Agreement shall be sufficient if in writing and (i) sent by email to the email address used by the CEO or by the Executive (as applicable) in their usual course of business; (ii) delivered by hand; (iii) sent by a nationally recognized overnight courier service or (iv) sent by registered or certified mail, postage prepaid, return receipt requested, in each case ((iii) and (iv)) to the Executive at the last address the Executive has filed in writing with the Company, or (as applicable) to the Company at its main office, attention of the CEO.