EX-99.1 2 exhibit_99.txt JOINT FILER INFORMATION Exhibit 99.1 Joint Filer Information Date of Event Requiring Statement: May 18, 2007 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 By: /s/ Peter G. Peterson ------------------------- Peter G. Peterson By: /s/ Stephen A. Schwarzman ------------------------- Stephen A. Schwarzman