Document:

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                                                                   Exhibit 10.12

                  TAX ALLOCATION AND INDEMNIFICATION AGREEMENT

     This Agreement is made this ____ day of _________, 2002 by and between
American Financial Corporation, an Ohio corporation (hereinafter called "AFC"),
and each and every one of those companies set forth on the signature page hereof
(collectively referred to as the "NSA Group Subsidiaries");

                                   WITNESSETH:

     WHEREAS, as a result of AFC's direct or indirect ownership of at least 80%
of the voting power of all classes of outstanding stock of each of the NSA Group
Subsidiaries, AFC and the NSA Group Subsidiaries have comprised an affiliated
group (hereinafter "Affiliated Group"), as that term is defined under Section
1504 of the Internal Revenue Code of 1954, as amended; and

     WHEREAS, each of the NSA Group Subsidiaries has satisfied its federal
income tax obligations by payments to (or receiving benefits from) AFC pursuant
to an Agreement of Allocation of Payment of Federal Income Taxes dated May 13,
1974, (the "Tax Allocation Agreement") and;

     WHEREAS, the Tax Allocation Agreement specifies that such federal income
tax obligations be computed with respect to GAAP income.

     WHEREAS, the NSA Group Subsidiaries' parent company, Infinity Property and
Casualty Corporation, has filed a registration statement under the Securities
Act for the purpose of selling a portion of its common stock indirectly owned by
AFC; and

     WHEREAS, upon completion of the public offering, the NSA Group Subsidiaries
will no longer be members of the Affiliated Group; and

     WHEREAS, AFC and the NSA Group Subsidiaries wish to provide for each of
their respective responsibilities and indemnification obligations with respect
to the payment of federal income taxes for taxable periods ending on or before
the completion of the public offering (the "Closing Date").

     NOW, THEREFORE, in consideration of the mutual promises and covenants
contained herein, AFC and the NSA Group Subsidiaries do hereby agree as follows:

     (1) Each member's allocable federal income tax will be determined by
reference to, and consistent with the methodology employed under, the Tax
Allocation Agreement.

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     (2) AFC shall be responsible for, shall pay all taxes to be paid, and shall
indemnify the NSA Group Subsidiaries against any and all pre-closing federal
income taxes imposed on the Affiliated Group that would have been allocated to
members of the Affiliated Group, other than the NSA Group Subsidiaries, for
taxable periods or portions thereof ending on or before the Closing Date. In the
case of federal income taxes attributable to taxable periods beginning on or
before and ending after the Closing Date ("Straddle") if any, the taxes for the
pre-closing period shall be computed as if such taxable period ended on the date
of the Closing.

     (3) The NSA Group Subsidiaries shall be responsible for, shall pay all
taxes to be paid, and shall indemnify AFC against any and all pre-closing
federal income taxes imposed on the Affiliated Group that would have been
allocated to the NSA Group Subsidiaries for taxable periods or portions thereof
ending on or before the Closing Date. AFC shall include the income of the NSA
Group Subsidiaries for the pre-closing period in the Affiliated Group's federal
consolidated tax returns, and shall file and be responsible for remitting all
taxes reflected on such consolidated returns. AFC shall prepare and file all
federal tax returns required to be filed by or with respect to the Affiliated
Group for periods ending on or before or including the Closing Date and shall
pay all federal income taxes due with respect thereto.

     (4) Any refunds of federal income taxes with respect to taxes allocated to
the NSA Group Subsidiaries and paid for any period ending on or before the
Closing Date shall be for the account of the NSA Group Subsidiaries. AFC shall,
if the NSA Group Subsidiaries so requests and at the NSA Group Subsidiaries'
expense, cause the relevant entity to file for and obtain any refunds to which
the NSA Group Subsidiaries are entitled hereunder, including through the
prosecution of an administrative or federal proceeding which the NSA Group
Subsidiaries, at their discretion, choose to direct such entity to pursue. AFC
shall permit the NSA Group Subsidiaries to participate in, but not control (at
the NSA Group Subsidiaries' expense), the prosecution of any such refund claimed
and when deemed appropriate by AFC, shall cause a relevant entity to authorize
by appropriate power of attorney such persons as the NSA Group Subsidiaries
shall designate to represent such entity with respect to such refund claim.
Without imposing any duty of investigation upon AFC, AFC shall, and shall cause
its affiliated members, to notify the NSA Group Subsidiaries of the existence of
any facts known to the Affiliated Group that would constitute a reasonable basis
for claiming a refund of taxes to which the NSA Group Subsidiaries are entitled
hereunder. AFC shall forward to the NSA Group Subsidiaries any such refund
promptly after the refund is received.

     (5) AFC shall promptly notify the NSA Group Subsidiaries in writing upon
receipt by AFC or any of its affiliate members, of notice of any pending or
threatened audit, assessment, or judicial administrative proceeding involving
taxes with respect to the Affiliated Group for which the NSA Group Subsidiaries
would be required to indemnify AFC pursuant to Section (3) above, provided the
failure of AFC to give such notice shall not relieve the NSA Group Subsidiaries
of its indemnification obligations under Section (3), except to the extent the
NSA Group Subsidiaries is materially prejudiced thereby.

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     (6) The NSA Group Subsidiaries shall promptly notify AFC in writing upon
receipt by the NSA Group Subsidiaries of notice of any pending or threatened
audit, assessment, or judicial administrative proceeding involving taxes with
respect to the NSA Group Subsidiaries for which AFC would be required to
indemnify the NSA Group Subsidiaries pursuant to Section (2) above, provided the
failure of the NSA Group Subsidiaries to give such notice shall not relieve AFC
of its indemnification obligations under Section (2), except to the extent AFC
is materially prejudiced thereby.

     (7) The NSA Group Subsidiaries shall have the right to participate in, but
not control, at their own expense, a tax proceeding to the extent it relates to
pre-closing taxes which may be the subject of indemnification by the NSA Group
Subsidiaries pursuant to Section (3) and to employ counsel of its choice at its
expense. AFC shall not compromise or settle any such tax proceeding without the
prior written consent of the NSA Group Subsidiaries, which consent shall not be
unreasonably withheld. If AFC shall not assume the defense of such tax
proceeding, then the NSA Group Subsidiaries may assume sole control over such
tax proceeding, at its own expense, without relieving the NSA Group Subsidiaries
of its indemnification obligation under Section (3).

     (8) AFC shall have the right to control, at its own expense, a tax
proceeding to the extent it relates to pre-closing taxes which may be the
subject of indemnification by AFC pursuant to Section (2) and to employ counsel
of its choice at its expense.

     IN WITNESS WHEREOF, this Agreement is hereby made effective on the date and
year first above written by the undersigned.

                                        AMERICAN FINANCIAL
                                          CORPORATION

                                        BY:
                                            ------------------------------------

                                        NSA GROUP SUBSIDIARIES

                                        ATLANTA CASUALTY COMPANY

                                        BY:
                                            ------------------------------------

                                        LEADER INSURANCE COMPANY

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                                        4

                                        BY:
                                            ------------------------------------

                                        INFINITY INSURANCE COMPANY

                                        BY:
                                            ------------------------------------

                                        WINDSOR INSURANCE COMPANY

                                        BY:
                                            ------------------------------------<PAGE>
                                                                    Exhibit 4.1

PREFERRED SHARES                                                PREFERRED SHARES
    NUMBER                                                            SHARES

----------------                                                ----------------
     PB
----------------                                                ----------------

                  DEVELOPERS DIVERSIFIED REALTY CORPORATION

THIS CERTIFICATE IS TRANSFERABLE IN                            CUSIP 251591 85 5
     CLEVELAND, OH                                          SEE REVERSE SIDE FOR
                                                             CERTAIN DEFINITIONS
INCORPORATED UNDER THE LAWS OF
     THE STATE OF OHIO

THIS CERTIFIES THAT

IS THE OWNER OF

FULLY PAID AND NONASSESSABLE 9 3/8% CUMULATIVE REDEEMABLE VOTING PREFERRED
SHARES, WITHOUT PAR VALUE ($25.00 LIQUIDATION PERFERENCE PER SHARE), OF

Developers Diversified Realty Corporation transferable on the books of the
Corporation by the holder hereof in person or by duly authorized attorney upon
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 Amended and Restated Articles of Incorporation and amendments
thereto as filed in the office of the Secretary of State of Ohio, to which the
holder by acceptance hereof, assents.  This certificate is not valid unless
countersigned and registered by the Transfer Agent and Registrar.

        In Witness Whereof, the Corporation has caused this certificate to be
executed by the facsimile signatures of its duly authorized officers.

COUNTERSIGNED AND REGISTERED:
           NATIONAL CITY BANK
               TRANSFER AGENT AND REGISTRAR

BY:                                 /s/ Joan U. Allgood   /s/ Scott A. Wolstein
       AUTHORIZED SIGNATURE            SECRETARY          CHAIRMAN OF THE BOARD

                             CERTIFICATE OF STOCK
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                  DEVELOPERS DIVERSIFIED REALTY CORPORATION

        The Preferred Shares represented by this certificate are subject to
restrictions on transfer for the purpose of the Corporation's maintenance of its
status as a Real Estate Investment Trust under the Internal Revenue Code of
1986, as amended.  Subject to certain provisions of the Corporation's Amended
and Restated Articles of Incorporation, as amended, no Person may Beneficially
Own or Constructively Own shares of any series of any class of Preferred Shares
in excess of 9.8% of the outstanding Preferred Shares of such series. Any
Person who attempts to Beneficially Own or Constructively Own shares of any
series of any class of Preferred Shares in excess of the above limitations
must immediately notify the Corporation. All capitalized terms in this legend
have the meanings defined in the Corporation's Amended and Restated Articles of
Incorporation, as amended, a copy of which, including the restrictions on
transfer, will be sent without charge to each shareholder who so requests.  If
the restrictions on transfer are violated, certain of the Preferred Shares
represented hereby may be subject to repurchase by the Corporation on the terms
and conditions set forth in the Corporation's Amended and Restated Articles of
Incorporation, as amended.

        The following abbreviations when used in the instructions 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__________
TEN ENT --as tenants by the entireties                           (Cust)             (Minor)
JT TEN  --as joint tenants with right of                    under Uniform Gifts to Minors
          survivorship and not as tenants                   Act_____________________
          in common
</Table>
    Additional abbreviations may also be used though not in the above list.

                                  ASSIGNMENT

        For value received,______________________________________________ hereby
sell(s), assign(s) and transfer(s) unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
   IDENTIFYING NUMBER OF ASSIGNEE
---------------------------------------

---------------------------------------

________________________________________________________________________________

________________________________________________________________________________

_______________________________________________________________ Preferred Shares
represented by the within Certificate, and do hereby irrevocably constitute and
appoint

_______________________________________________________________________ Attorney
to transfer the said Preferred Shares on the books of the within named
Corporation with full power of substitution in the premises.

Dated:__________________________________

________________________________________________________________________________
NOTICE: The signature to the assignment must correspond with the name as written
upon the face of this Receipt in every particular, without alteration or
enlargement or any change whatever.

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