EX-99 4 exh99.txt JOINT FILER INFORMATION Exhibit 99.1 Joint Filer Information Date of Event Requiring Statement: January 19, 2005 Issuer Name and Ticker or Trading Symbol: Celanese Corporation (CE) Designated Filer: Blackstone LR Associates (Cayman) IV Ltd. Other Joint Filers: Blackstone Capital Partners (Cayman) Ltd.1, Blackstone Capital Partners (Cayman) Ltd.2, Blackstone Capital Partners (Cayman) Ltd.3, Peter G Peterson, Stephen A Schwarzman Addresses: The principal business address of each of the Joint Filers above is c/o The Blackstone Group, 345 Park Avenue, New York, New York 10154 Signatures: Blackstone Capital Partners (Cayman) Ltd.1 By: /s/ Robert L. Friedman --------------------------- Name: Robert L. Friedman Title: Director Blackstone Capital Partners (Cayman) Ltd.2 By: /s/ Robert L. Friedman --------------------------- Name: Robert L. Friedman Title: Director Blackstone Capital Partners (Cayman) Ltd.3 By: /s/ Robert L. Friedman --------------------------- Name: Robert L. Friedman Title: Director /s/ Robert L. Friedman, as Attorney in Fact -------------------------- Peter G. Peterson /s/ Robert L. Friedman, as Attorney in Fact -------------------------- Stephen A. Schwarzman