<Page>


               (FACE OF CINERGY CORP. COMMON STOCK CERTIFICATE)


COMMON STOCK                                 THIS CERTIFICATE IS TRANSFERABLE
                                                IN THE CITY OF CINCINNATI
                                               OR IN THE CITY OF NEW YORK


INCORPORATED UNDER THE LAWS                  CUSIP 172474 10 8
 OF THE STATE OF DELAWARE                    SEE REVERSE FOR CERTAIN DEFINITIONS

                                             N U M B E R

                                             S H A R E S




                                  CINERGY CORP.



This Certifies that ____________________ is the owner of _____________________.

     FULLY-PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK OF THE PAR VALUE OF
$0.01 EACH, OF

CINERGY CORP. TRANSFERABLE ON THE BOOKS OF THE CORPORATION BY THE HOLDER HEREOF
IN PERSON OR BY DULY AUTHORIZED ATTORNEY UPON THE SURRENDER OF THIS CERTIFICATE
PROPERLY ENDORSED. THIS CERTIFICATE AND THE SHARES REPRESENTED HEREBY ARE ISSUED
AND SHALL BE HELD SUBJECT TO ALL THE PROVISIONS OF THE CERTIFICATE OF
INCORPORATION OF THE CORPORATION AND ALL AMENDMENTS THERETO FILED IN THE OFFICE
OF THE SECRETARY OF STATE OF DELAWARE, COPIES OF WHICH ARE ON FILE WITH THE
TRANSFER AGENT, TO ALL OF WHICH THE HOLDER BY ACCEPTANCE HEREOF ASSENTS. THIS
CERTIFICATE IS NOT VALID UNLESS COUNTERSIGNED BY A TRANSFER AGENT AND REGISTERED
BY A REGISTRAR.

     WITNESS THE FACSIMILE SEAL OF THE CORPORATION AND THE SIGNATURES OF ITS
DULY AUTHORIZED OFFICERS.


<Table>

<S>                                              <C>
DATED:                                                          CINERGY CORP.

                                                 COUNTERSIGNED:
      CHAIRMAN OF THE BOARD, PRESIDENT                      CINERGY SERVICES, INC.
        AND CHIEF EXECUTIVE OFFICER                           (Cincinnati, Ohio)
                                                 BY                                     TRANSFER AGENT

           CORPORATE SECRETARY                                                    AUTHORIZED SIGNATURE
                                                 REGISTERED:
                                                             THE FIFTH THIRD BANK,
                                                              (Cincinnati, Ohio)
                                                 BY                                          REGISTRAR

                                                                                  AUTHORIZED SIGNATURE

</Table>

                                  CINERGY CORP.
                                    CORPORATE
                                      SEAL
                                      1993
                                    DELAWARE

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           (REVERSE OF CINERGY CORP. COMMON STOCK CERTIFICATE)

This certificate also evidences and entitles the holder hereof to certain Rights
as set forth in the Rights Agreement between Cinergy Corp. and the Rights Agent
thereunder (the "Rights Agreement"), the terms of which are hereby incorporated
herein by reference and a copy of which is on file at the principal offices of
Cinergy Corp. Under certain circumstances, as set forth in the Rights Agreement,
such Rights will be evidenced by separate certificates and will no longer be
evidenced by this certificate. Cinergy Corp. will mail to the holder of this
certificate a copy of the Rights Agreement, as in effect on the date of mailing
without charge promptly after receipt of a written request therefor. Under
certain circumstances set forth in the Rights Agreement, Rights issued to, or
held by, any Person who is, was or becomes an Acquiring Person or any Affiliates
or Associates thereof (as such terms are defined in the Rights Agreement),
whether currently held by or on behalf of such Person on by any subsequent
holder, may become null and void.

                              CINERGY CORP.

Cinergy Corp. will mail to the record holder of this certificate, without
charge, within five days after receipt of written request therefor, addressed to
the Secretary of the Corporation, P.O. Box 900, Cincinnati, Ohio 45201, a copy
of the express terms of the shares represented by this certificate and of other
classes and shares which the Corporation is authorized to issue.

         The following abbreviations, when used in the inscription on the face
of this Certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:


<Table>

         <S>                                          <C>
         TEN COM  -  as tenants in common             UNIF GIFT MIN ACT - _________Custodian__________
                                                                           (Cust)            (Minor)
         TEN ENT  -  as tenants by the entireties                         under Uniform Gifts to Minors
                                                                          Act_________________________
         JT TEN   -  as joint tenants with right of                                  (State)
                     survivorship and not as tenants
                     in common                        UNIF TRAN MIN ACT - _________Custodian__________
                                                                           (Cust)            (Minor)
         TOD      -  transfer on death                                    under Uniform Transfers to Minors
                                                                          Act_________________________
                                                                                     (State)

</Table>

         Additional abbreviations may also be used though not in the above list.

         FOR VALUE RECEIVED, ____________________ HEREBY SELL, ASSIGN AND
TRANSFER UNTO-

PLEASE INSERT SOCIAL SECURITY OR OTHER
   IDENTIFYING NUMBER OF ASSIGNEE
_____________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________
      (PLEASE PRINT OR TYPEWRITE NAME, ADDRESS AND ZIP CODE OF ASSIGNEE)

_______________________________________________________________________ SHARES
OF THE CAPITAL STOCK REPRESENTED BY THE WITHIN CERTIFICATE, AND DO HEREBY
IRREVOCABLY CONSTITUTE AND APPOINT
____________________________________________________________ ATTORNEY TO
TRANSFER THE SAID STOCK ON THE BOOKS OF THE WITHIN-NAMED CORPORATION, WITH FULL
POWER OF SUBSTITUTION IN THE PREMISES.

DATED __________________________
                                      X __________________________________
              NOTICE:                              (SIGNATURE)

       THE SIGNATURE(S) TO THIS
       ASSIGNMENT MUST CORRE-
       SPOND WITH THE NAME(S)
       AS WRITTEN UPON THE FACE
       OF THE CERTIFICATE IN EVERY
       PARTICULAR WITHOUT ALTER-
       ATION OR ENLARGEMENT OR ANY
       CHANGE WHATEVER.
                                      X __________________________________
                                                   (SIGNATURE)

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THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN "ELIGIBLE GUARANTOR INSTITUTION" AS
DEFINED IN RULE 17Ad-15 UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

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SIGNATURE(S) GUARANTEED BY:









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