Citigroup (C) POSASR Automatic shelf registration (post-effective amendment)

Exhibit 4.05

CERTIFICATE OF TRUST

OF

CITIGROUP CAPITAL XXIII

     This Certificate of Trust is being executed as of November 15, 2007 for the purposes of organizing a statutory trust pursuant to the Delaware Statutory Trust Act, 12 Del. C. §3801 et seq. (the “Act”).

     The undersigned, the trustees of Citigroup Capital XXIII, hereby certify as follows:

     1. Name. The name of the statutory trust being formed hereby is “Citigroup Capital XXIII” (the “Trust”).

     2. Delaware Trustee. The name and business address of the trustee of the Trust which has its principal place of business in the State of Delaware are as follows:

The Bank of New York (Delaware)
100 White Clay Center
Route 273
P. O. Box 6995
Newark, DE 19711

     3. Effective. This Certificate of Trust shall be effective immediately upon filing in the Office of the Secretary of State of the State of Delaware.

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Dated: November 15, 2007

By:	/s/ John Gerspach
John Gerspach, as Regular Trustee
By:	/s/ Eric L. Wentzel
Eric L. Wentzel, as Regular Trustee
By:	/s/ Saul Rosen
Saul Rosen, as Regular Trustee
THE BANK OF NEW YORK (DELAWARE),
as Delaware Trustee
By:	/s/ Kristine K. Gullo
Name: Kristine K. Gullo
Title: Vice President
CITIGROUP INC.,
as Sponsor
By:	/s/ Charles E. Wainhouse
Name: Charles E. Wainhouse
Title: Vice President

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