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                             SUPPLEMENTAL INDENTURE

     This Supplemental Indenture (this "SUPPLEMENTAL INDENTURE"), dated as of
May 31, 2001, by and among FMRP Inc. (the "GUARANTEEING SUBSIDIARY"), a
subsidiary of IMC Global Inc., a Delaware corporation (the "COMPANY"), the
Company and The Bank of New York, as trustee under the Indenture referred to
below (the "TRUSTEE").

                                W I T N E S E T H

     WHEREAS, the Company has heretofore executed and delivered to the Trustee
an indenture (the "SEVEN YEAR INDENTURE"), dated as of May 17, 2001 providing
for the issuance of an aggregate principal amount of up to $400 million of
10.875% Senior Notes due 2008 (the "SEVEN YEAR NOTES");

     WHEREAS, the Company has heretofore executed and delivered to the Trustee
an indenture (the "TEN YEAR INDENTURE" and together with the Seven Year
Indenture, the "INDENTURE"), dated as of May 17, 2001 providing for the issuance
of an aggregate principal amount of up to $200 million of 11.250% Senior Notes
due 2011 (the "TEN YEAR NOTES"and together with the Seven Year Notes, the
"NOTES");

     WHEREAS, Section 10.04 of the Indenture provides that, if a Person becomes
obligated to guarantee the Notes pursuant to the Indenture, the new guarantor
must execute a supplemental indenture to which such Guarantor shall
unconditionally guarantee all of the Company's obligations under the Notes and
the Indenture on the terms and conditions set forth herein and in the Indenture;

     WHEREAS, pursuant to Section 8.06 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

     NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the parties
hereto mutually covenant and agree for the equal and ratable benefit of the
Holders of the Notes as follows:

     1. CAPITALIZED TERMS. Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

     2. AGREEMENT TO GUARANTEE. The Guaranteeing Subsidiary hereby agrees to
become subject to the terms of the Indenture as a Guarantor.

     3. INCORPORATION OF TERMS OF INDENTURE. The obligations of the Guaranteeing
Subsidiary under the Note Guarantees shall be governed in all respects by the
terms of the Indenture and shall constitute a Note Guarantee thereunder. The
Guaranteeing Subsidiary shall be bound by the terms of the Indenture as they
relate to the Note Guarantees.



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     4. NO RECOURSE AGAINST OTHERS. No past, present or future director,
officer, employee, incorporator, stockholder or agent of the Guaranteeing
Subsidiary, as such, shall have any liability for any obligations of the Company
or the Guaranteeing Subsidiary under the Notes, any Note Guarantees, the
Indenture or this Supplemental Indenture or for any claim based on, in respect
of, or by reason of, such obligations or their creation. Each Holder of the
Notes by accepting a Note waives and releases all such liability. The waiver and
release are part of the consideration for issuance of the Notes. Such waiver may
not be effective to waive liabilities under the federal securities laws and it
is the view of the SEC that such a waiver is against public policy.

     5. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL
GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT WITHOUT GIVING
EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE
APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

     6. COUNTERPARTS. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

     7. EFFECT OF HEADINGS. The Section headings herein are for convenience only
and shall not affect the construction

hereof.

     8. TRUSTEE. The Trustee shall not be responsible in any manner whatsoever
for or in respect of the validity or sufficiency of this Supplemental Indenture
or for or in respect of the recitals contained herein, all of which recitals are
made solely by the Guaranteeing Subsidiary and the Company.



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     IN WITNESS WHEREOF, the parties hereto have caused this First Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

Dated: May 31, 2001

                                    IMC GLOBAL INC.

                                    By: /s/ J. Bradford James
                                        -------------------------------------
                                        Name: J. Bradford James
                                        Title: Executive Vice President & CFO


                                    FMRP INC.

                                    By:/s/ J. Bradford James
                                       --------------------------------------
                                        Name: J. Bradford James
                                        Title: Vice President


                                    THE BANK OF NEW YORK, AS TRUSTEE

                                    By: /s/ Mary LaGumina
                                        -------------------------------------
                                        Name: Mary LaGumina
                                        Title: Vice President