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                                                                   Exhibit 10(a)



                           KOCH TAX SHARING AGREEMENT


                  This Tax Sharing Agreement ("Agreement") is executed on this
____ day of ______, 2000 (the "Merger Date"), by and among Koch Industries, Inc.
("Koch"), PM Holdings Corporation ("Holdings"), the subsidiaries of Holdings
listed on Schedule I and their successors and assigns hereto (the "Holdings
Subsidiaries").

                                    RECITALS
                                    --------

         1. Koch is the parent of an affiliated group of companies, as defined
in section 1504(a) of the Internal Revenue Code of 1986 (the "Code"), that files
consolidated federal income tax returns (the "Affiliated Group"). Holdings and
the Holdings Subsidiaries (Holdings and the Holdings Subsidiaries are referred
to herein collectively as the "Holdings Sub-Group") are members of the
Affiliated Group. The Holdings Sub-Group became part of the Affiliated Group as
a result of Koch Agriculture Company's acquisition of Holdings on March 12,
1998; the members of the Holdings Sub-Group (each a "Holdings Member") were
included in the Affiliated Group's federal income tax return for the first time
for the taxable year ending December 31, 1998.

         2. On March 12, 1998, Koch and Holdings entered into the Parent Tax
Sharing Agreement.

         3. On October 28, 1999, several Holdings Members (the "Debtors") filed
for bankruptcy under chapter 11 of the Bankruptcy Code. Pursuant to and in
connection with the described filing for bankruptcy, on January 18, 2000, the
Debtors filed a Joint Plan of Reorganization of Purina Mills, Inc. ("PMI"), Its
Parent Corporation, and Its Debtor Subsidiaries (the "Plan").

         4. On the date of execution of this Agreement, Purina Mills, Inc.
merged with and into its sole shareholder, Holdings (the "Merger"), pursuant to
the Plan.


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         5. As of the Effective Date of the Plan, the outstanding stock of
Holdings will be canceled, and the Holdings Sub-Group will leave the Affiliated
Group.

         6. It is the intent and desire of the parties hereto that agreement be
reached (a) on the allocation of responsibility for payment of, or the right to
refunds of, the federal, state, local and foreign consolidated or combined
income tax liability (including penalties and interest thereon) ("Taxes") of the
Affiliated Group between the Holdings Sub-Group, on the one hand, and the
members of the Affiliated Group other than the Holdings Sub-Group (the "Koch
Entities"), on the other; (b) on certain matters regarding any Taxes
attributable to each Non-Affiliated Taxable Period, as hereinafter defined; and
(c) on the rights and responsibilities of each party hereto with respect to
certain administrative matters relating to Taxes.

                                    AGREEMENT
                                    ---------

         Now, therefore, in consideration of the mutual covenants and promises
contained herein, the parties hereto agree as follows:

         1. PARENT TAX SHARING AGREEMENT. Koch hereby waives any and all claims,
matured and unmatured, that it might have against the Holdings Sub-Group and
each Holdings Subsidiary under the Parent Tax Sharing Agreement. Holdings and
each Holdings Subsidiary hereby waive any and all claims, matured and unmatured,
that they might have against the Koch Entities under the Parent Tax Sharing
Agreement. This Agreement supersedes the Parent Tax Sharing Agreement in all
respects; as of the Effective Date, the Parent Tax Sharing Agreement shall be of
no further force or effect.

         2. NON-AFFILIATED TAXABLE PERIODS. None of the Koch Entities shall have
any responsibility whatsoever for the payment of Taxes due from any Holdings
Member for any taxable period during which the Holdings Sub-Group was not or is
not part of the Affiliated Group (a "Non-Affiliated Taxable Period"), and
Holdings hereby agrees to indemnify and hold harmless each of the Koch Entities
with respect to any such Taxes. Similarly, no Holdings Member shall have any
responsibility whatsoever for the payment of Taxes due from any one of



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the Koch Entities for any Non-Affiliated Taxable Period, and Koch hereby agrees
to indemnify and hold harmless each Holdings Member with respect to any such
Taxes.

         3. FILING OF RETURNS FOR AFFILIATED TAXABLE PERIODS. For all taxable
periods during which the Holdings Sub-Group is part of the Affiliated Group
(each an "Affiliated Taxable Period"), Koch shall cause consolidated federal
income tax returns (each a "Koch Consolidated Return") and estimated tax returns
for the Affiliated Group to be prepared and filed. All Holdings Members shall
execute and file such consents, elections, and other documents as Koch
determines are required or appropriate for the proper filing of such returns and
shall furnish to Koch any and all information reasonably requested by Koch in
order to carry out the provisions of this paragraph. For all Affiliated Taxable
Periods, Holdings shall cause to be prepared hypothetical estimated and final
federal income tax returns showing the estimated and final federal income tax
liability of the Holdings Sub-Group, calculated as if the Holdings Sub-Group
filed a separate consolidated return.

         4. ALLOCATION OF TAX LIABILITY. Koch and the Holdings Members agree
that the Affiliated Group's consolidated federal income tax liability,
determined in accordance with Treas. Regs. ss. 1.1502-2, for each Affiliated
Taxable Period shall be apportioned between the Koch Entities as a group and the
Holdings Sub-Group (each a "Member") in accordance with the provisions of Treas.
Regs. ss. 1.1552-1(a)(2) and 1.1502-33(d)(2). Any Taxes attributable to the
Affiliated Taxable Period within which the Effective Date falls shall be
allocated, using a closing-of-the-books method, between the period during which
the Holdings Members are members of the Affiliated Group and the period during
which the Holdings Members are not members of the Affiliated Group, and any
Taxes attributable to the first period (but not those attributable to the
second) shall be apportioned using the method of allocation described herein.
The consolidated federal tax liability of the Affiliated Group shall be
allocated to each of the two Members on the basis of the percentage of the total
tax that the tax of such Member (if computed on a separate return basis) would
bear to the total amount of taxes for both Members so computed pursuant to
section 1552(a)(2) of the Code and Treas. Regs. ss. 1.1552-1(a)(2). In


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computing the tax that it would owe on a separate return basis for the period
ending on the Effective Date, the Holdings Sub-Group shall take into account any
items of gain or loss that will in fact be triggered to any Holdings Member
under Treas. Reg. Section 1.1502-13 or section 267(f) of the Code upon the
departure of the Holdings Sub-Group from the Affiliated Group as of the
Effective Date (other than an item generated by the transaction described in
section IV.B.3.b of the Plan). If a Member (the "Tax Attribute Member") is
unable to absorb a tax attribute on a separate return basis in one year but is
able to absorb that attribute on a separate return basis in a subsequent year in
which it continues to be a part of the Affiliated Group, a portion of the
consolidated tax liability which otherwise would have been allocated to the Tax
Attribute Member in the subsequent year under Treas. Regs. Section
1.1552-1(a)(2) will instead be reallocated to the other Member of the Affiliated
Group using the principles of Treas. Regs. Section 1.1502-33(d)(2). This
allocation, including the effect of any reallocation, shall be each Member's
"Allocated Tax Liability" for that year. For purposes of this Agreement, the
consolidated tax liability shall include any liability for alternative minimum
tax.

         5. PAYMENT OF TAX. For all Affiliated Taxable Periods, Holdings and the
Holdings Subsidiaries shall be jointly and severally liable to pay to Koch no
later than 10 days before the date on which the Koch Consolidated Return is
required to be filed (giving effect to any extensions thereof) the separate
return tax liability of the Holdings Sub-Group determined pursuant to Treas.
Regs. Sections 1.1552-1(a)(2)(ii) and 1.1502-33(d)(2) plus its ratable
share of any interest or penalties shown as due on the Koch Consolidated Return
(determined by multiplying such interest or penalties by a fraction, the
numerator of which equals the Holdings Sub-Group's Allocated Tax Liability
(before interest or penalties) and the denominator of which equals the
Affiliated Group's tax liability (before interest or penalties)).

         6. CARRYFORWARD/CARRYBACK OF LOSSES AND CREDITS. If part or all of an
unused loss or tax credit is allocated to a Member pursuant to Treas. Regs.
Section 1.1502-21 and is carried back or forward to a Non-Affiliated Taxable
Year, any refund or reduction in tax liability arising from the carryback or
carryforward shall be retained by such Member. Notwithstanding the foregoing,


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Koch shall determine whether an election shall be made (i) not to carry back any
portion of any such loss arising in an Affiliated Taxable Year (including any
portion allocated to a Member under Treas. Regs. Section 1.1502-21) in
accordance with section 172(b)(3) of the Code, or (ii) to reattribute to itself
any portion of any loss attributable to the disposition of the stock of any
Holdings Member, to the extent permitted by Treas. Regs. Section 1.1502-20(g).
The Holdings Members agree to join with Koch in filing any necessary elections
under Treas. Regs. Section 1.1502-20(g) to reflect such reattribution.

         7. ESTIMATED TAX PAYMENTS. If the Affiliated Group is required to make
estimated federal income tax payments (including payments due at the time any
extension of time is sought for the filing of the Koch Consolidated Return),
Holdings shall, if requested by Koch, pay to Koch, no later than 10 days before
the date such estimated tax payment is to be made by Koch, that percentage of
the estimated tax payment that equals the percentage which the estimated
Allocated Tax Liability of the Holdings Sub-Group for the taxable period or year
to which such estimated tax payment relates bears to the aggregate estimated tax
liability of the Affiliated Group for such taxable period or year. Such
estimates shall be determined by Koch in good faith after reviewing relevant
information provided to Koch by Holdings. Any estimated tax payments made by
Holdings under this paragraph 7 with respect to any taxable period shall be
applied to reduce the amount, if any, owed by Holdings under paragraph 4 hereof
with respect to such period. Any excess of such estimated payments by Holdings
over the amount described in paragraph 5 for such taxable period shall be repaid
by Koch to Holdings no later than 10 days after the date of filing of the Koch
Consolidated Return for such taxable period or, to the extent such excess
represents all or a part of a tax refund to be received by the Affiliated Group,
no later than 10 days after the receipt of the refund.

         8. ADJUSTMENTS TO TAX LIABILITY. If the consolidated tax liability of
the Affiliated Group is adjusted for any Affiliated Taxable Period, whether
pursuant to an amended return, a claim for refund, a tax audit by the Internal
Revenue Service (the "IRS") or for some other reason, the liability of each
Member shall be recomputed in accordance with the principles of this



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Agreement to give effect to such adjustments, and, in the case of a refund, Koch
shall make payment to Holdings for the Holdings Sub-Group's share of the refund,
determined in the same manner as in paragraph 4 above, within 10 days after the
refund is received by Koch. In the case of an increase in tax liability, the
Holdings Sub-Group shall pay to Koch the Holdings Sub-Group's allocable share of
such increased tax liability (including interest and penalties but excluding the
taxes with respect to which Koch has indemnified the Holdings Sub-Group under
paragraph 9(b) of this Agreement), reduced to the extent that the Holdings
Sub-Group generated any attributes during an Affiliated Taxable Period that it
was previously unable to absorb on a separate return basis, if the Holdings
Sub-Group would have been able to use such adjusted income attributed to it to
absorb such attributes, in accordance with the provisions of paragraph 4 hereof,
in the taxable year being adjusted. Such payment, if any, will be made within 10
days after receiving notice of such liability from Koch. The parties recognize
that a recomputation of the consolidated tax liability for any taxable year
under this paragraph 8 is not necessarily the final liability for such year, and
such liability may be recomputed more than once.

         9.       INDEMNITY FOR ASSESSMENT OF SEPARATE ENTITY TAXES.

                  (a)      Notwithstanding any provision of this Agreement to
                           the contrary, Koch hereby agrees to indemnify and
                           hold harmless each and every member of the Holdings
                           Sub-Group with respect to any Taxes (and for any
                           foreign, state, and local taxes, including penalties
                           and interest thereon not subsumed within the term
                           "Taxes") collected from any members thereof to the
                           extent that such Taxes would have properly been
                           attributable to the consolidated federal taxable
                           income of the Koch Entities computed as if the
                           Holdings Sub-Group was not a member of Affiliated
                           Group.

                  (b)      Koch hereby agrees to indemnify and hold harmless
                           each and every Holdings Member with respect to Taxes
                           (and for any foreign, state and local taxes,
                           including penalties and interest thereon, not
                           subsumed within the term "Taxes"), if any, imposed by
                           any taxing authority with respect to the



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                           separately calculated taxable income of any Holdings
                           Member as a result of the implementation of sections
                           III.C.3, III.C.6, and IV.B.3.b of the Plan.
                           Notwithstanding the immediately preceding sentence,
                           in no case shall this indemnity extend to Taxes (or
                           to any foreign, state and local taxes, including
                           penalties and interest thereon, not subsumed within
                           the term "Taxes"), if any, attributable to: (i)
                           income or gain of one or more Holdings Members
                           recognized (but deferred and taken into account under
                           Treasury Regulation Section 1.1502-13, or under
                           similar principles of foreign, state or local tax
                           law, as a result of the departure of the Holdings
                           Sub-Group from the Affiliated Group) in connection
                           with any intercompany transaction (other than the
                           transaction described in section IV.B.3.b of the
                           Plan) completed prior to the Effective Date of the
                           Plan; (ii) income or gain of any Holdings Subsidiary
                           arising out of the implementation of sections III.C.3
                           or III.C.6 of the Plan; (iii) income or gain of
                           Holdings arising out of the implementation of
                           sections III.C.3 or III.C.6 of the Plan other than
                           income or gain resulting solely from Holdings'
                           previous inclusion in the Affiliated Group; or (iv)
                           income or gain that would not otherwise have existed
                           had Restructuring Transactions (as that term is
                           defined in the Plan), other than the transaction
                           described in section IV.B.3.b of the Plan, not been
                           carried out.

                  (c)      Notwithstanding any other provision of this Agreement
                           to the contrary and except as provided in the
                           immediately preceding subsection (b), Holdings and
                           the Holdings Subsidiaries each hereby agree to
                           indemnify and hold harmless the Koch Entities with
                           respect to any Taxes (and for any foreign, state and
                           local taxes, including penalties and interest thereon
                           not subsumed within the term "Taxes") collected from
                           the Koch Entities to the extent that such Taxes would
                           have properly been attributable to the consolidated
                           federal taxable income of the Holdings Sub-Group
                           computed as if the Holdings Sub-Group



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                           constituted a separate consolidated group for federal
                           income tax purposes, provided, however, that in no
                           event will Holdings or any Holdings Subsidiary have
                           any obligation under this paragraph 9(c) to indemnify
                           any Koch Entity for Taxes against which the Holdings
                           Members are indemnified pursuant to paragraph 9(b) of
                           this Agreement, and provided further that, in
                           computing the Taxes that would have been attributable
                           to the Holdings Sub-Group, effect shall be given to
                           any attributes generated by the Holdings Sub-Group or
                           any Holdings Subsidiary during any Affiliated Taxable
                           Period that the Holdings Sub-Group was previously
                           unable to absorb on a separate return basis.

         10.      CLAIMS FOR INDEMNIFICATION.

                  (a)      Any claim for indemnification under this Agreement
                           shall be made in writing, along with proof of the
                           final determination of the Taxes for which a claim is
                           made, and the indemnifying party shall reimburse the
                           indemnified party for the full amount of such
                           assessment within 10 days of receiving such notice.
                           For these purposes, a "final determination" shall
                           mean any administrative or judicial determination
                           that an amount of Taxes is due and owing, to the
                           extent such determination is not subject to any
                           further administrative or judicial appeal.

                  (b)      In calculating the amount of any claim for
                           indemnification under this Agreement, it shall be
                           assumed that (i) payments received in the form of
                           indemnification represent payment by the indemnifying
                           party of its own joint and several liability for
                           taxes of the Affiliated Group and as such will not be
                           subject to tax, (ii) in the event, after a final
                           determination, such payments in the form of
                           indemnification have been determined to be taxable,
                           then and only then shall the indemnifying party make
                           an additional payment to the indemnified party, such
                           that the total amount received pursuant to this
                           paragraph 10, reduced by the amount of tax paid


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                           thereon, shall equal the amount originally paid by
                           the indemnified party which gave rise to the claim
                           for indemnification pursuant to this paragraph 10 as
                           increased by any related deficiency interest and
                           penalties imposed on the indemnified party by the
                           taxing authority, but only to the extent that such
                           interest and penalties would not have been imposed
                           had the amount originally paid by the indemnifying
                           party been timely reported to such taxing authority
                           as taxable income.

                  (c)      Notwithstanding any provision hereof to the contrary,
                           Koch shall not be responsible for the payment of any
                           claim for indemnification unless the claimant (i)
                           shall notify Koch of the proposed assessment of such
                           tax, penalties, or interest at a time and in a manner
                           that affords Koch a meaningful opportunity to
                           contest, compromise or settle any such proposed
                           assessment, (ii) shall, upon contact by an examining
                           agent or officer of the taxing authority for the
                           purpose of conducting an examination, notify such
                           agent or officer of the identity of the parent of the
                           Affiliated Group and request that such agent or
                           officer deal directly with said parent as the agent
                           for the Affiliated Group, (iii) shall cooperate fully
                           with Koch's efforts to contest, compromise or settle
                           any such proposed assessment, and (iv) prior to any
                           payment of tax giving rise to such claim for
                           indemnification, shall provide a copy of the
                           collection notice or other bill reflecting the amount
                           due to the taxing authority following a final
                           determination of such tax liability and shall have
                           provided a 30-day period (or such reasonable lesser
                           period as required to allow the party requesting
                           indemnity to make payment on such notice or bill in
                           the event Koch does not exercise its exclusive right
                           under this subsection (iv) of paragraph 10(c))
                           immediately following the provision of such notice or
                           bill, prior to



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                           and during which the indemnifying party shall have
                           had the exclusive right to make payment directly to
                           such taxing authority.

                  (d)      Notwithstanding any provision of this paragraph 10 to
                           the contrary, no Holdings Member shall be responsible
                           for the payment of any claim for indemnification
                           unless Koch (i) shall notify Holdings of the proposed
                           assessment of such tax, penalties, or interest and
                           (ii) shall make a good faith effort to contest any
                           such proposed assessment.

         11. REPORTING THE MERGER. All parties hereto agree that, on any return
filed by the Affiliated Group, Koch or the Holdings Sub-Group, the party or
parties filing such return shall report the transaction described in section
IV.B.3.b of the Plan as a reorganization described in section 368(a)(1) of the
Code as to which, pursuant to sections 354(a) and 361, no gain or loss is
recognized by Holdings or any Holdings Subsidiary in connection with that
transaction. Except as otherwise provided in this Agreement, no party to this
Agreement may take a position contrary to that described in the preceding
sentence on any return or in the course of any audit, dispute, proceeding or
action.

         12. TERM OF AGREEMENT. All terms of this Agreement shall first take
effect on the date or dates set forth in Section 20 below and shall continue in
effect with respect to all Affiliated Taxable Periods, except that the
provisions of paragraphs 2, 9, 11, 14(c), 14(d), and 14(e) shall continue in
effect with respect to all taxable periods.

         13. POST-CONSOLIDATED GROUP PERIOD. The Koch Entities and each Holdings
Member shall cooperate fully and to the extent reasonably requested by each
other in connection with the preparation and filing of any tax return or the
conduct of any audit, dispute, proceeding or action concerning any issues or any
other matter contemplated hereunder. Such cooperation shall include, without
limitation, the retention and provision upon demand of books, records,
documentation or other information (including, without limitation, returns,
supporting schedules, work papers, correspondence and other documents) relating
to the tax liability of the



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Affiliated Group or any Holdings Member for any taxable year in which such
member was included in the Affiliated Group. The obligation to retain records
and provide them upon reasonable request shall not terminate until the
expiration of all applicable statutes of limitation (giving effect to any
extension, waiver or mitigation thereof).

         The Koch Entities and each Holdings Member shall furnish each other
information and assistance required and take all steps necessary to apply for
and obtain the benefit of any carryback of a net operating or capital loss or
any investment, foreign tax or other credit of a Holdings Member for an
Affiliated Taxable Period.
         The parties hereto also agree to execute any document that may be
necessary or helpful in connection with the filing of any tax return by the
Affiliated Group or any Holdings Member or in connection with any tax-related
(i) audit, (ii) dispute, (iii) proceeding or (iv) action, any of which involve
the Affiliated Group or any Holdings Member, and to use their best efforts to
obtain any documentation from a governmental authority or a third party that may
be necessary or helpful in connection with the foregoing. Koch and Holdings will
cause each member of the Affiliated Group and of the Holdings Sub-Group to make
its employees and facilities available on a mutually convenient basis to
facilitate the cooperation required hereunder and will retain as permanent
records all documentation necessary to enable it to determine any obligation
under this Agreement.

         14.      AUDITS AND REFUND CLAIMS.

                  (a)      Koch shall be the sole and exclusive agent of the
                           Affiliated Group with respect to any and all matters
                           relating to the federal income tax liability of the
                           Affiliated Group. Except as provided in the
                           immediately following subsection, Koch shall have the
                           right (i) to contest, compromise or settle any
                           adjustment or deficiency proposed, asserted, or
                           assessed by the IRS and (ii) to decide whether to
                           file and how to prosecute, compromise or settle any
                           claim for refund on behalf of the Affiliated



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                           Group. Except as provided in the immediately
                           following subsection, Koch shall have the right to
                           make the final determination as to the response of
                           the Affiliated Group to any audit and shall have the
                           sole right to control, at its own expense, any
                           contest of any change proposed and any proposed
                           disallowance of a refund claim by the IRS through
                           Examination, the Appeals Office of the IRS, and the
                           courts in connection with any Affiliated Taxable
                           Period.

                  (b)      In the event of an audit, dispute, proceeding or
                           action involving the proper tax treatment of any item
                           or items reported by any Holdings Member for any
                           Affiliated Taxable Period (other than items which
                           could give rise to taxes against which the Holdings
                           Members are indemnified pursuant to paragraph 9(b) of
                           this Agreement), Koch (i) shall provide the affected
                           Holdings Subsidiary with a meaningful opportunity to
                           comment on and propose revisions to any
                           communications that Koch proposes to provide to any
                           governmental authority relating to the treatment of
                           such item or items, (ii) shall not unreasonably
                           reject any revisions proposed by the affected
                           Holdings Subsidiary, and (iii) shall not compromise
                           or settle any such issue on any basis other than "as
                           filed" on the tax return without written approval
                           from the affected Holdings Subsidiary, such consent
                           not to be unreasonably withheld.

                  (c)      In the event of an audit, dispute, proceeding or
                           action involving the proper tax treatment of any
                           transaction that is or was part of the Plan on a tax
                           return of the Holdings Sub-Group or any Holdings
                           Subsidiary for a Non-Affiliated Taxable Period, the
                           Holdings Sub-Group or the affected Holdings
                           Subsidiary (i) shall make all reasonable efforts to
                           support and uphold in all administrative proceedings
                           and in litigation the treatment given to such
                           transaction on its return as filed pursuant to the
                           requirements of paragraph 11 hereof, (ii) shall
                           provide Koch with a meaningful opportunity to comment
                           on and propose revisions to any communications



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                           that the Holdings Sub-Group or affected Holdings
                           Subsidiary proposes to provide to any governmental
                           authority relating to the treatment of such
                           transaction, (iii) shall not unreasonably reject any
                           revisions proposed by Koch hereunder, and (iv) shall
                           not compromise or settle any such issue on any basis
                           other than "as filed" on the tax return without
                           written approval from Koch, such consent not to be
                           unreasonably withheld.

                  (d)      Koch and each Holdings Member shall use reasonable
                           efforts to keep each other advised as to the status
                           of any tax audits, disputes or litigation involving
                           any issue which relates in any way to any transaction
                           described in the Plan or which could affect the tax
                           treatment of any transaction described in the Plan.
                           Koch and each Holdings Member shall each promptly
                           notify the other of any inquiries by any taxing
                           authority or other administrative, judicial or other
                           governmental authority, to the extent that such
                           inquiries relate in any way to any transaction
                           described in the Plan or which could affect the tax
                           treatment of any transaction described in the Plan.
                           Each party hereto shall promptly furnish to each
                           other party a copy of those portions of any notices
                           of proposed adjustment, revenue agent's reports, or
                           notices of deficiency that relate to any matter that
                           could affect such other party's tax liability.

                  (e)      Notwithstanding any provision herein to the contrary,
                           in the event of any change in applicable law, after
                           the effective date of such change, no party shall be
                           required to file any return treating any item in a
                           manner not then permitted by law.

         15.      Representations and Warranties.

                  (a)      Koch's Representations and Warranties.

                           i.       Koch represents and warrants that as of the
                                    Merger Date:



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                           (a)      All tax returns, reports, information
                                    returns or other documents (including any
                                    related or supporting information and, where
                                    applicable, profit and loss accounts and
                                    balance sheets) ("Tax Returns") required to
                                    be filed by Koch on behalf of Holdings have
                                    been timely filed with the appropriate
                                    governmental authorities. All Taxes shown to
                                    be due on any such Tax Returns have been
                                    timely paid or, if applicable, withheld and
                                    paid to the appropriate taxing authority in
                                    the manner provided by law.

                           (b)      To the best of Koch's knowledge, all Tax
                                    Returns required to be filed by Holdings
                                    during any Affiliated Taxable Period have
                                    been timely filed with the appropriate
                                    governmental authorities, and all Taxes
                                    shown to be due on any such Tax Returns have
                                    been timely paid or, if applicable, withheld
                                    and paid to the appropriate taxing authority
                                    in the manner provided by law.

                           (c)      Except as shown on Schedule II hereto, to
                                    the best of Koch's knowledge there are no
                                    federal, state, local or foreign audits,
                                    administrative proceedings or court
                                    proceedings pending with regard to any Taxes
                                    of Holdings relating to any Affiliated
                                    Taxable Period or Tax Returns of Holdings
                                    relating to any Affiliated Taxable Period,
                                    and there are no outstanding deficiencies or
                                    assessments with respect thereto that have
                                    been asserted or proposed.

                           (d)      To the best of Koch's knowledge, Holdings is
                                    not a party to any agreement providing for
                                    the allocation or sharing of Taxes



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                  other than the Parent Tax Sharing Agreement and the Sub-Group
                  Tax Sharing Agreement executed on March 12, 1998.

                  (e)      Koch has not filed on Holdings' behalf a consent to
                           the application of section 341(f) of the Code.

                  ii. For a period of one year after the Effective Date, Koch
                  shall indemnify and hold harmless any and all Holdings Members
                  against any costs or expenses of any sort whatever (including
                  attorneys' fees) arising out of or resulting from any breach
                  of any representation or warranty of Koch set forth in this
                  section.

         (b)      Holdings Representations and Warranties.

                  i. Holdings represents and warrants that:

                           (a)      Following the completion of the transaction
                                    described in section IV.B.3.b of the Plan,
                                    Holdings will either (i) continue one or
                                    more significant historic businesses of PMI
                                    in a manner that satisfies the requirements
                                    of Treas. Reg. Sec. 1.368-1(d)(2) or (ii)
                                    use a significant portion of PMI's historic
                                    business assets in the conduct of a trade or
                                    business in a manner that satisfies the
                                    requirements of Treas. Reg. Sec.
                                    1.368-1(d)(3).

                           (b)      None of Holdings, its officers, directors,
                                    or subsidiaries has any plan or intention to
                                    take any action, or fail to take any action,
                                    that would result in Holdings' failure to
                                    satisfy the continuity of business
                                    enterprise requirement of Treas. Reg. Sec.
                                    1.368-1(d) with respect to the transaction
                                    described in section IV.B.3.b of the Plan.

                  ii. If gain is recognized by PMI in connection with the
                  transaction described in section IV.B.3.b of the Plan that,
                  but for a violation of the immediately preceding warranty and
                  representation by Holdings, would not have been recognized by
                  PMI, then, any provision of this Agreement to the contrary



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                  notwithstanding, each Koch Entity shall be released from any
                  and all obligations created in this Agreement to indemnify
                  Holdings in respect of any Tax attributable to such gain.

         16. SETTLEMENT OF DISPUTES. A dispute or difference between any Koch
Entity and any Holdings Member with respect to the operation or interpretation
of this Agreement shall be decided by three arbitrators. Koch and Holdings shall
each select one arbitrator and the arbitrators selected by the parties shall
select a third arbitrator. The decision of such arbitrators shall be final. The
Koch Entities and the Holdings Members respectively shall be jointly and
severally liable for one-half the fees of such arbitrators.

         17. ELECTIONS. Koch shall have the sole authority to make any and all
Affiliated Group elections available under the Code, Treasury regulations and
any applicable state or local income tax code, law or statute.

         18. FOREIGN, STATE AND LOCAL INCOME TAXES. The principles underlying
the rights and obligations hereunder of the Members in respect of federal income
taxes shall be applied in respect of any foreign, state or local tax (however
denominated) of the Affiliated Group or any of its members (a "Non-Federal
Tax"). All of the procedural and timing requirements of this Agreement
applicable to federal income taxes shall be equally applicable to any
Non-Federal Tax, with appropriate adjustments thereto to reflect the
differences, if any, in corresponding provisions of the applicable income tax
code, law or statute governing any such Non-Federal Tax and any administrative
provisions relating thereto.

         19. ENTIRE AGREEMENT. This Agreement contains the entire understanding
of the parties hereto with respect to the subject matter contained herein. No
alteration, amendment or modification of any of the terms of this Agreement
shall be valid unless made by an instrument signed in writing by an authorized
officer of each party.

         20. BINDING AGREEMENT AND EFFECTIVE DATE.

                  (b)      This Agreement shall be binding upon and inure to the
                           benefit of each party hereto and its respective
                           successors and assigns.



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<PAGE>   17

                  (c)      The provisions of this Agreement shall only be in
                           force and become effective on the Effective Date of
                           the Plan, except that the provisions contained in the
                           waiver provision of paragraph 1 (with respect to any
                           claims arising out of matters subject to the
                           indemnity provided in paragraph 9(b) hereof),
                           paragraph 9(b), and paragraph 11 shall be effective
                           as of the Merger Date.

         21. GOVERNING LAW. This Agreement shall be governed by and interpreted
in accordance with the laws of the State of Delaware.

         22. COUNTERPARTS. This Agreement may be executed simultaneously in two
or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.



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