SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13G*
                                 (Rule 13d-102)

                           INFORMATION TO BE INCLUDED
                          IN STATEMENTS FILED PURSUANT
                           TO RULES 13d-1(b), (c), AND
                           (d) AND AMENDMENTS THERETO
                          FILED PURSUANT TO RULE 13d-2
                                (AMENDMENT NO. 3)*

                              Cemex, S.A.B. de C.V.
--------------------------------------------------------------------------------
                                (Name of Issuer)

                       Ordinary Participation Certificates
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                  P2253T-13-3
            --------------------------------------------------------
                                 (CUSIP Number)

                               December 31, 2012
--------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

   / /       Rule 13d-1(b)
   /X/       Rule 13d-1(c)
   / /       Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section
of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).


                                     Page 1
                                   of 6 Pages



                                       13G

CUSIP NO.  P2253T-13-3                                        Page 2 of 6 Pages


-------------------------------------------------------------------------------
 (1) NAMES OF REPORTING PERSONS

     Citigroup Inc.
-------------------------------------------------------------------------------
 (2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

                                                                       (a)  / /
                                                                       (b)  / /
-------------------------------------------------------------------------------
 (3) SEC USE ONLY



-------------------------------------------------------------------------------
 (4) CITIZENSHIP OR PLACE OF ORGANIZATION                              Delaware



-------------------------------------------------------------------------------
       NUMBER OF           (5) SOLE VOTING POWER                              0

        SHARES
                           ----------------------------------------------------
     BENEFICIALLY          (6) SHARED VOTING POWER                 399,224,277*
                                                                             **
       OWNED BY
                           ----------------------------------------------------
        EACH               (7) SOLE DISPOSITIVE POWER                         0

      REPORTING
                           ----------------------------------------------------
       PERSON              (8) SHARED DISPOSITIVE POWER            399,224,277*
                                                                             **
        WITH:
-------------------------------------------------------------------------------
(9) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON   399,224,277*
                                                                             **




-------------------------------------------------------------------------------
(10) CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE
     INSTRUCTIONS)  / /


-------------------------------------------------------------------------------
(11) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)                    3.7%*
                                                                             **



-------------------------------------------------------------------------------
(12) TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)                             HC


-------------------------------------------------------------------------------
*   The percentage held is based on 10,816,160,000 shares of Ordinary
    Participation Certificates outstanding. The reporting person's holdings
    consist of 27,117,941 American Depositary Shares (each representing 10
    Ordinary Participation Certificates) and 128,044,863 Ordinary Participation
    Certificates.
**  Assumes conversion/exercise of certain securities held.




Item 1(a).     Name of Issuer:

               Cemex, S.A.B. de C.V.

Item 1(b).     Address of Issuer's Principal Executive Offices:

               Avenida Ricardo Margain Zozaya #325
               Colonia Valle del Campestre
               Garza Garcia, Nuevo Leon
               Mexico 66265

Item 2(a).     Name of Person Filing:

               Citigroup Inc. ("Citigroup")

Item 2(b).     Address of Principal Business Office or, if none, Residence:

               The address of the principal business office of Citigroup is:

               399 Park Avenue
               New York, NY 10022

Item 2(c).     Citizenship:

               Citigroup is a Delaware corporation.

Item 2(d).     Title of Class of Securities:

               Ordinary Participation Certificates

Item 2(e).     CUSIP Number:

               P2253T-13-3


                                     Page 3
                                   of 6 Pages


Item 3.      If This Statement Is Filed Pursuant to Sections 240.13d-1(b) or
             240.13d-2(b) or (c), Check Whether the Person Filing Is a(n):

             (a)  [ ] Broker or dealer registered under Section 15 of the
                      Act (15 U.S.C. 78o);

             (b)  [ ] Bank as defined in Section 3(a)(6) of the Act
                      (15 U.S.C. 78c);

             (c)  [ ] Insurance company as defined in Section 3(a)(19) of
                      the Act (15 U.S.C. 78c);

             (d)  [ ] Investment company registered under Section 8 of the
                      Investment Company Act of 1940 (15 U.S.C. 80a-8);

             (e)  [ ] Investment adviser in accordance with Section
                      240.13d-1(b)(1)(ii)(E);

             (f)  [ ] Employee benefit plan or endowment fund in accordance
                      with Section 240.13d-1(b)(1)(ii)(F);

             (g)  [ ] Parent holding company or control person in accordance
                      with Section 240.13d-1(b)(1)(ii)(G);

             (h)  [ ] Savings association as defined in Section 3(b) of the
                      Federal Deposit Insurance Act (12 U.S.C. 1813);

             (i)  [ ] Church plan that is excluded from the definition of an
                      investment company under Section 3(c)(14) of the
                      Investment Company Act of 1940 (15 U.S.C. 80a-3);

             (j)  [ ] A non-U.S. institution in accordance with Section
                      240.13d-1(b)(1)(ii)(J);

             (k)  [ ] Group, in accordance with Section 240.13d-1(b)(1)(ii)(K).
                      If filing as a non-U.S. institution in accordance with
                      Section 240.13d-1(b)(1)(ii)(J), please specify the type
                      of institution: ____________________________ .


Item 4.   Ownership. (as of December 31, 2012)

          (a)  Amount beneficially owned: See item 9 of cover pages

          (b)  Percent of class: See item 11 of cover pages

          (c)  Number of shares as to which the person has:

                  (i)   Sole power to vote or to direct the vote:

                  (ii)  Shared power to vote or to direct the vote:

                  (iii) Sole power to dispose or to direct the disposition of:

                  (iv)  Shared power to dispose or to direct the disposition of:


                  See Items 5-8 of cover pages


                                     Page 4
                                   of 6 Pages


Item 5.   Ownership of Five Percent or Less of a Class.

          If this statement is being filed to report the fact that as of the
          date hereof the reporting person has ceased to be the beneficial owner
          of more than five percent of the class of securities, check the
          following [X].

Item 6.   Ownership of More Than Five Percent on Behalf of Another Person.

          Not Applicable.

Item 7.   Identification and Classification of the Subsidiary Which Acquired
          the Security Being Reported on by the Parent Holding Company.

          See Exhibit 1 for the identity and classification of the relevant
          subsidiaries which directly beneficially own the securities reported
          herein.

Item 8.   Identification and Classification of Members of the Group.

          Not Applicable.

Item 9.   Notice of Dissolution of Group.

          Not Applicable.



                                     Page 5
                                   of 6 Pages



Item 10.  Certification.

     By signing  below I certify  that,  to the best of my knowledge and belief,
the  securities  referred  to above were not  acquired  and are not held for the
purpose  of or with the efect of  changing  or  influencing  the  control of the
issuer of the  securities  and were not acquired and are not held in  connection
with or as a participant in any transaction having that purpose or effect.

SIGNATURE.

          After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement is true,
complete and correct.

Dated: February 13, 2013


                      CITIGROUP INC.



                      By: /s/ Ali L. Karshan
                         --------------------------------------------
                         Name:   Ali L. Karshan
                         Title:  Assistant Secretary




                                     Page 6
                                   of 6 Pages




                          EXHIBIT INDEX TO SCHEDULE 13G
                          -----------------------------



EXHIBIT 1
---------

Identification and Item 3 Classification of the subsidiaries which acquired the
securities being reported by the parent holding companies.