0001306830-24-000108 4 1 20240512 20240514 20240514 Brown William M 0001350633 4 34 001-32410 24945772 HARRIS CORPORATION 1025 W NASA BOULEVARD MELBOURNE FL 32919 Celanese Corp 0001306830 2820 08 Industrial Applications and Services 980420726 DE 1231 222 W. LAS COLINAS BLVD., SUITE 900N IRVING TX 75039-5421 972-443-4000 222 W. LAS COLINAS BLVD., SUITE 900N IRVING TX 75039-5421 Celanese CORP 20041102 Blackstone Crystal Holdings Capital Partners (Cayman) IV Ltd. 20041022 4 1 wk-form4_1715721474.xml FORM 4 X0508 4 2024-05-12 0 0001306830 Celanese Corp CE 0001350633 Brown William M C/O CELANESE CORPORATION 222 W LAS COLINAS BLVD, SUITE 900N IRVING TX 75039 1 0 0 0 0 Common Stock 2024-05-12 4 D 0 1777 D 103 D Phantom Stock 2024-05-12 4 A 0 1777 0 A Common Stock 1777 14769.315 D Phantom Stock 2024-05-13 4 A 0 56.757 160.24 A Common Stock 56.757 14826.072 D Upon vesting of 1,777 Restricted Stock Units granted to the reporting person on May 12, 2023, the reporting person deferred the receipt of 1,777 shares of Common Stock and received instead 1,777 shares of phantom stock pursuant to the Company's 2008 Deferred Compensation Plan (the "Plan"). As a result, the reporting person is reporting the disposition of 1,777 shares of Common Stock in exchange for an equal number of shares of phantom stock. Each share of phantom stock represents the right to receive one share of Common Stock. As provided in the Plan, the reported phantom stock becomes payable in shares of Common Stock upon termination of the reporting person's service as a director of the Company subject to certain restrictions and limitations. Each share of phantom stock represents the right to receive one share of Common Stock or the cash value of one share of Common Stock. The reported phantom stock represents dividend equivalents on cash compensation and restricted stock units deferred under the Plan. As provided by the Plan, the reporting person may transfer a portion of the phantom stock account into an alternative investment account at any time. The shares of phantom stock become payable in cash or shares of Common Stock, subject to certain conditions and as provided in the Plan, on the earlier of the date previously elected by the reporting person to receive payment or upon termination of the reporting person's service as a director of the Company. /s/ Adam R. Santosuosso, Attorney-in-Fact for William M. Brown 2024-05-14