POT Potash Corp. of Saskatchewan Inc. (delisted)

DESCRIPTION OF THE NOTES

The following description of the particular terms of the notes offered by this prospectus supplement adds information to the description of the general terms and provisions of debt securities under the heading “Description of Debt Securities” beginning on page 5 of the accompanying prospectus. As used under “Prospectus Supplement Summary — The Offering” and under this heading, “Description of the Notes,” all references to “we,” “us,” “our,” “PotashCorp” and the “Company” refer to Potash Corporation of Saskatchewan Inc. excluding any of its subsidiaries.

General

We will initially issue the notes in the aggregate principal amount of $        pursuant to an indenture dated as of February 27, 2003 between us and U.S. Bank National Association (as successor trustee to The Bank of Nova Scotia Trust Company of New York), the trustee for the notes. The notes will mature on                 ,          . We will initially issue the notes only in registered book-entry form, in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

The notes will bear interest at the annual rate shown on the cover of this prospectus supplement and will accrue interest from                 , 2016 or from the most recent date to which interest has been paid (or provided for) to but not including the next date upon which interest is required to be paid.

Commencing                 , 2017, interest will be payable twice a year, on                  and                 , to the person in whose name a note is registered at the close of business on the          or          that precedes the date on which interest will be paid. Interest on the notes will be paid on the basis of a 360-day year consisting of twelve 30-day months.

If any interest payment date or maturity date falls on a day that is not a business day, the payment will be made on the next succeeding business day with the same force and effect as if made on the relevant interest payment date or maturity date and no interest will accrue for that period from and after the applicable interest payment date or maturity date.

As contemplated under “Description of Debt Securities — Discharge, Defeasance and Covenant Defeasance” on page 15 of the accompanying prospectus, the satisfaction of certain conditions will permit us to discharge some or all of our obligations under the indenture with respect to the notes. In addition, we may discharge our obligations with respect to certain covenants through covenant defeasance. We refer you to the information under “Description of Debt Securities — Discharge, Defeasance and Covenant Defeasance” in the accompanying prospectus for more information.

Except as described in this prospectus supplement or the accompanying prospectus, the indenture for the notes does not contain any covenants or other provisions designed to protect holders of the notes against a reduction in our creditworthiness in the event of a highly leveraged transaction nor does the indenture for the notes prohibit other transactions that might adversely affect holders of the notes, including the incurrence of additional indebtedness. See “Risk Factors — We will make only limited covenants in the indenture for the notes” in this prospectus supplement.

Re-opening of the Notes

We are initially offering the notes in the aggregate principal amount of $        . We may from time to time, without the consent of the holders of the notes, create and issue further notes having the same terms and conditions in all respects as the notes being offered hereby, except for the date of issue, the initial price, the first date from which interest will accrue, and, in some cases, the first payment of interest thereon. Additional notes issued in this manner will be consolidated with and will form a single series with the notes being offered hereby if such issuance is fungible with this issuance for U.S. federal income tax purposes.

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Optional Redemption

At any time prior to the Par Call Date, the notes will be redeemable, in whole or in part, at our option at any time and from time to time at a redemption price equal to the greater of:

plus accrued and unpaid interest on the principal amount being redeemed to the date of redemption.

At any time on or after the Par Call Date, the notes will be redeemable, in whole or in part, at our option at any time and from time to time at a redemption price equal to 100% of the principal amount of the notes to be redeemed plus accrued and unpaid interest on the principal amount being redeemed to the date of redemption.

Notwithstanding the foregoing, installments of interest on notes that are due and payable on interest payment dates falling on or prior to a redemption date will be payable on the interest payment date to the registered holders as of the close of business on the relevant record date according to the notes and the indenture.

In connection with such optional redemption, the following defined terms apply:

“Adjusted Treasury Rate” means, with respect to any redemption date, the rate per annum equal to the semi-annual equivalent yield to maturity (computed as of the third business day immediately preceding that redemption date) or interpolated (on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for that redemption date.

“Comparable Treasury Issue” means the United States Treasury security or securities selected by the Independent Investment Banker that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the notes to be redeemed (assuming, for this purpose, that the notes matured on the Par Call Date).

“Comparable Treasury Price” means, with respect to any redemption date, (a) the average of the Reference Treasury Dealer Quotations for that redemption date, after excluding the highest and lowest of such Reference Treasury Dealer Quotations, or (b) if the Independent Investment Banker for the notes obtains fewer than five such Reference Treasury Dealer Quotations, the average of all such quotations.

“Independent Investment Banker” means one of the Reference Treasury Dealers appointed by us to act as the “Independent Investment Banker.”

“Par Call Date” means                 ,          (three months prior to the maturity date of the notes).

“Reference Treasury Dealer” means (a) Goldman, Sachs & Co., Morgan Stanley & Co. LLC, RBC Capital Markets, LLC or Scotia Capital (USA) Inc. and their respective affiliates or successors, and one other nationally recognized investment banking firm that is a primary U.S. Government securities dealer in New York City (a “ Primary Treasury Dealer” ) specified from time to time by us; provided, however, that if any of the foregoing shall cease to be a Primary Treasury Dealer, we shall substitute therefor another nationally recognized investment banking firm that is a Primary Treasury Dealer or (b) any other Primary Treasury Dealer selected by us.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Independent Investment Banker, of the bid and asked prices

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for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Independent Investment Banker by such Reference Treasury Dealer at 3:30 p.m., New York City time, on the third business day preceding that redemption date.

“Remaining Scheduled Payments” means, with respect to each note to be redeemed, the remaining scheduled payments of the principal thereof and interest thereon that would be due if such notes matured on the Par Call Date but for such redemption; provided, however, that, if that redemption date is not an interest payment date with respect to such note, the amount of the next succeeding scheduled interest payment thereon will be reduced by the amount of interest accrued thereon to that redemption date.

Notice of any redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each holder of the notes to be redeemed. On and after any redemption date, interest will cease to accrue on the notes or any portion thereof called for redemption. On or before any redemption date, we shall deposit with the trustee or with a paying agent money sufficient to pay the redemption price of and accrued interest on the notes to be redeemed on such date. If less than all of the notes are to be redeemed, the notes to be redeemed shall be selected by the trustee at our direction by such method as we and the trustee shall deem fair and appropriate. The redemption price shall be calculated by the Independent Investment Banker and we, the trustee and any paying agent for the notes shall be entitled to rely on such calculation.

Redemption for Changes in Withholding Taxes

The notes will be redeemable, at our option, at any time as a whole but not in part, upon not less than 30 nor more than 60 days prior written notice to the holders (with a copy to the trustee, paying agent and transfer agent), at a redemption price equal to 100% of their aggregate principal amount, plus any additional amounts, as described in the accompanying prospectus under “Description of Debt Securities — Certain Covenants —Additional Amounts”, and accrued and unpaid interest to the date of redemption (subject to the right of holders of record on a relevant record date to receive interest due on the respective interest payment date), in the event there is a substantial probability that we have become or would become obligated to pay, on the next date on which any amount would be payable with respect to the notes, any additional amounts as a result of:

which change or amendment is publicly announced or becomes effective on or after the date of this prospectus supplement (or the date a party organized in a jurisdiction other than Canada becomes our successor).

The notice of redemption referred to below may not be given earlier than 90 days prior to the earliest date on which we would be obligated to pay such additional amounts were a payment in respect of the notes then due and payable. Any such redemption described in this section shall be consummated upon not less than 30 days nor more than 60 days’ prior written notice.

Before we publish or mail a notice of redemption of the notes as described in this section, we will deliver to the trustee an officers’ certificate to the effect that we are entitled to redeem the notes pursuant to the terms of the indenture and such notice shall not be effective until the Company delivers to the trustee an opinion of counsel to the effect that there is a substantial probability that additional amounts will be payable on the next payment date in respect of the notes as a result of a Change in Tax Law. We will, prior to or contemporaneously with the

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publication or mailing of any notice of redemption of any notes as described in this section, furnish to the trustee, paying agent and transfer agent a copy of such notice of redemption.

Change of Control

If a Change of Control Triggering Event occurs with respect to the notes, unless we have exercised our right to redeem the notes as described above, we will be required to make an offer to repurchase all, or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof), of each holder’s notes pursuant to the offer described below (the “Change of Control Offer” ) on the terms set forth in the notes. In the Change of Control Offer, we will be required to offer payment in cash equal to 101% of the aggregate principal amount of notes repurchased plus accrued and unpaid interest, if any, on the notes repurchased, to the date of purchase (the “Change of Control Payment” ).

Within 30 days following any Change of Control Triggering Event, we will be required to mail a notice to holders of the notes describing the transaction or transactions that constitute the Change of Control Triggering Event and offering to repurchase the notes on the date specified in the notice, which date will be no earlier than 30 days and no later than 60 days from the date such notice is mailed (the “Change of Control Payment Date” ), pursuant to the procedures required by the notes and described in such notice. We must comply with the requirements of Rule 14e-1 under the Securities Exchange Act of 1934, as amended (the “Exchange Act” ), and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of the notes as a result of a Change of Control Triggering Event. To the extent that the provisions of any applicable securities laws or regulations conflict with the Change of Control provisions of the notes, we will be required to comply with the applicable securities laws and regulations and will not be deemed to have breached our obligations under the Change of Control provisions of the notes by virtue of such conflicts.

On the Change of Control Payment Date, we will be required, to the extent lawful, to:

The paying agent will be required to mail promptly to each holder who properly tendered notes the purchase price for such notes and the trustee will be required to authenticate and mail (or cause to be transferred by book entry) promptly to each such holder a new note equal in principal amount to any unpurchased portion of the notes surrendered, if any; provided that each new note will be in a principal amount of $2,000 or an integral multiple of $1,000 in excess thereof.

For purposes of the foregoing discussion of a repurchase at the option of holders, the following definitions are applicable:

“Below Investment Grade Rating Event” means the rating on the notes is changed from an Investment Grade Rating to below an Investment Grade Rating by each of the Rating Agencies (as defined below) on any date from the date of the public notice of an arrangement that could result in a Change of Control until the end of the 60-day period following public notice of the occurrence of the Change of Control (which 60-day period shall be extended so long as the rating of the notes is under publicly announced consideration for possible downgrade by any of the Rating Agencies).

“Change of Control” means the occurrence of any of the following: (1) the direct or indirect sale, transfer, conveyance or other disposition (other than by way of merger, amalgamation, arrangement or consolidation), in

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one or a series of related transactions, of all or substantially all of our properties or assets and those of our subsidiaries taken as a whole to any Person other than us or one of our subsidiaries; (2) the consummation of any transaction (including, without limitation, any merger, amalgamation, arrangement or consolidation) the result of which is that any Person becomes the beneficial owner, directly or indirectly, of more than 50% of the total voting power in the aggregate of all classes of our voting stock normally entitled to vote in elections of directors; or (3) the first day on which a majority of the members of our Board of Directors are not Continuing Directors. The Proposed Transaction shall not constitute a Change of Control with respect to the notes for purposes of the indenture.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Below Investment Grade Rating Event.

“Continuing Directors” means, as of any date of determination, any member of our Board of Directors who (1) was a member of such Board of Directors on the date of this prospectus supplement; or (2) was nominated for election or elected to such Board of Directors with the approval of a majority of the Continuing Directors who were members of such Board of Directors at the time of such nomination or election (either by a specific vote or by approval of our proxy statement in which such member was named as a nominee for election as a director, without objection to such nomination).

“Investment Grade Rating” means a rating equal to or higher than Baa3 (or the equivalent) by Moody’s and BBB- (or the equivalent) by S&P or the equivalent investment grade rating from any additional Rating Agency or Rating Agencies.

“Moody’s” means Moody’s Investors Service, Inc.

“Person” means any individual, partnership, corporation, limited liability company, joint stock company, business trust, trust, unincorporated association, joint venture or other entity, or a government or political subdivision or agency thereof.

“Rating Agencies” means (1) each of Moody’s and S&P; and (2) if either Moody’s or S&P ceases to rate the notes or fails to make a rating of the notes publicly available for reasons outside of our control, a “nationally recognized statistical rating organization” as defined in Section 3(a)(62) of the Exchange Act, selected by us (as certified by a resolution of our Board of Directors) as a replacement agency for Moody’s or S&P, or both of them, as the case may be.

“S&P” means Standard & Poor’s Ratings Services, a division of The McGraw-Hill Companies, Inc.

The failure by us to comply with the obligations described under “— Change of Control” will constitute an event of default with respect to the notes.

Financial Information

The indenture provides that as long as any notes are outstanding, we will file with the trustee, within 15 days after we file the same with the Commission, copies of the annual reports and the information, documents and other reports which we may be required to file with the Commission pursuant to Section 13 or Section 15(d) of the Exchange Act or, if we are not required to file information, documents or reports pursuant to either of such sections of the Exchange Act, then we will file with the trustee, in accordance with the rules and regulations of the Commission, such of the supplementary and periodic information, documents and reports which may be required pursuant to Section 13 of the Exchange Act in respect of a security listed and registered on a national securities exchange.

Book-Entry System

The certificates representing the notes will initially be issued in the form of one or more fully registered global notes without coupons (a “ Global Note ”) and will be deposited with, or on behalf of, DTC and registered

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in the name of Cede & Co., as the nominee of DTC. Except in limited circumstances, the notes will not be issuable in definitive form. Unless and until they are exchanged in whole or in part for the individual notes represented thereby, any interests in the Global Note may not be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any nominee of DTC to a successor depository or any nominee of such successor. In addition, transfers of beneficial interests in the Global Note will be subject to the applicable rules and procedures of DTC and its direct or indirect participants, including, if applicable, those of Euroclear and Clearstream, which may change from time to time. See “Legal Ownership of Debt Securities — Global Securities” in the accompanying prospectus.

DTC has advised us that DTC is a limited-purpose trust company organized under the New York Banking Law, a “banking organization” within the meaning of the New York Banking Law, a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code, and a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act. DTC holds securities that its participants (“ Direct Participants ”) deposit with DTC. DTC also facilitates the post-trade settlement among Direct Participants of sales and other securities transactions in deposited securities, through electronic computerized book-entry transfers and pledges between Direct Participants’ accounts. This eliminates the need for physical movement of securities certificates. Direct Participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations, and certain other organizations. DTC is a wholly owned subsidiary of The Depository Trust & Clearing Corporation (“ DTCC ”). DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others such as both U.S. and non-U.S. securities brokers and dealers, banks, trust companies and clearing corporations that clear through or maintain a custodial relationship with a Direct Participant, either directly or indirectly. The rules applicable to DTC and its participants are on file with the Commission.

The information in this section concerning DTC and DTC’s book-entry system has been obtained from sources that we believe to be reliable, but we take no responsibility for the accuracy thereof.

Same-Day Funds Settlement and Payment

Settlement for the notes will be made by the underwriters in immediately available funds. All payments of principal and interest in respect of notes in book-entry form will be made by us in immediately available funds to the accounts specified by DTC.

Secondary trading in long-term notes and debentures of corporate issuers is generally settled in clearing houses or next-day funds. In contrast, the notes will trade in DTC’s Same-Day Funds Settlement System until maturity, or earlier redemption or repayment, or until the notes are issued in certificated form, and secondary market trading activity in the notes will therefore be required by DTC to settle in immediately available funds, and transfers between participants in Euroclear and Clearstream will be effected in accordance with their respective rules and operating procedures. Cross-market transfers between the participants in DTC, on the one hand, and DTC participants acting on behalf of Euroclear or Clearstream participants, on the other hand, will be effected through DTC in accordance with DTC’s rules on behalf of DTC participants acting on behalf of Euroclear or Clearstream, as the case may be; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (Brussels time) of such system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to the DTC participant acting on its behalf to take action to effect final settlement on its behalf by delivering or receiving interests in the relevant Global Note in DTC, and making or receiving payment in accordance with normal procedures for same-day funds settlement applicable to DTC. Euroclear participants and Clearstream participants may not deliver instructions directly to the DTC participants acting on behalf of Euroclear or Clearstream. No assurance can be given as to the effect, if any, of settlement in immediately available funds on trading activity in the notes.

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Concerning the Trustee

U.S. Bank National Association (as successor to The Bank of Nova Scotia Trust Company of New York), is the trustee under the indenture. An affiliate of the trustee is a lender under our $3,500.0 million credit facility. The trustee and its affiliates may also maintain other normal banking relationships, including the maintenance of depositary accounts, with us and certain of our subsidiaries.

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DESCRIPTION OF DEBT SECURITIES

As required by U.S. federal securities law, the debt securities offered pursuant to this prospectus are governed by a document called an indenture. The indenture is a contract between us, as issuer, and U.S. Bank National Association, as successor trustee. The indenture is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part. The indenture is subject to and governed by the U.S. Trust Indenture Act of 1939, as amended. You should read the indenture for a more complete understanding of the provisions we describe below. Please see “Where You Can Find More Information” for information on how to obtain a copy of the indenture.

In the discussion that follows, we summarize certain provisions of the indenture. This discussion is not complete, and is qualified by reference to all the provisions of the indenture, including definitions of terms used in the indenture. For example, in this section we use defined terms that have been given special meaning in the indenture. We describe the meaning for only the more important terms. We also include references in parentheses to certain sections of the indenture. Whenever we refer to particular sections or defined terms of the indenture in this prospectus or in any related prospectus supplement, those sections or defined terms are incorporated by reference into this prospectus or into any related prospectus supplement, as applicable.

We describe in this section the general terms that will apply to any debt securities that may be offered by us pursuant to this prospectus. At the time that we offer debt securities, we will describe in the related prospectus supplement the specific terms of the offered debt securities and the extent to which the general terms described in this section apply to those debt securities.

General

We may from time to time sell the debt securities described in this prospectus in one or more foreign currencies, currency units or composite currencies. The indenture provides that debt securities may be issued thereunder in an unlimited amount. The debt securities may be issued in one or more series, as established by us or as established in one or more indentures supplemental to the indenture. Not all debt securities of one series need be issued at the same time and, unless otherwise provided, any series may be reopened, without the consent of the holders of the debt securities of that series, for issuances of additional debt securities of that series. ( Section 3.01 )

The debt securities described in this prospectus will be direct unsecured obligations of PotashCorp and will rank equally and ratably without preference among themselves and at least equally with all of our other unsecured and unsubordinated indebtedness.

The particular terms of each issue of debt securities, as well as any modifications or additions to the general terms of the indenture that may be applicable in the case of that issue of debt securities, will be described in the applicable prospectus supplement. This description will include, without limitation, where applicable:

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We may issue debt securities as original issue discount securities to be offered and sold at a substantial discount below their stated principal amounts. We will describe in the related prospectus supplement any special U.S. or Canadian federal income tax, accounting or other considerations that may apply to any such original issue discount securities.

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The prospectus supplement for each offering of debt securities may add to or change statements contained in this prospectus. Except as described in any related prospectus supplement, the debt securities will not contain any provisions that would limit our ability to incur unsecured indebtedness or that would afford holders of the debt securities protection in the event of a leveraged transaction or that would prohibit other transactions that could adversely affect holders of the debt securities.

Form, Denomination, Registration or Transfer

Unless otherwise specified in the applicable prospectus supplement, we will issue debt securities only in registered form.

We may issue debt securities of a series in whole or in part in the form of one or more global securities. (Section 2.03)

Unless otherwise specified in the applicable prospectus supplement, we will issue debt securities denominated in U.S. dollars in integral multiples of $1,000. We will specify the denomination of any series of debt securities denominated in a foreign or composite currency or currency units in the related prospectus supplement. If applicable, we will issue one or more global securities in a denomination or aggregate denominations equal to the aggregate principal amount of the outstanding debt securities of the series to be represented by such global security or securities. (Sections 3.01 and 3.02)

The trustee will act as our agent for registering debt securities in the names of holders and recording transfers of debt securities, although we may appoint another entity to perform this function or perform this function ourselves. The entity performing this function is called the “security registrar.” If other than the trustee, we will identify any such security registrar for a series of debt securities in the applicable prospectus supplement.

You may transfer or exchange debt securities at the office of the security registrar. You will not be required to pay any service charge for any registration of transfer or exchange of debt securities, but you may be required to pay for any tax or other governmental charge associated with the transfer or exchange. You may have your debt securities, other than a global security, exchanged for more debt securities of smaller permitted denominations or for fewer debt securities of larger permitted denominations. The transfer or exchange of a debt security will only be made if the security registrar is satisfied with your proof of ownership. (Section 3.05)

Neither we nor the trustee will be required to:

Global Debt Securities

We may issue the debt securities of a series in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the related prospectus supplement. Global securities will be registered in the name of the depositary or its nominee. Unless a global security is exchanged in whole or in part for debt securities in definitive form, a global security generally may be transferred only as a whole and only to the depositary or to a nominee of the depositary or to a successor depositary or its nominee. (Sections 3.01 and 3.05)

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A general description of global securities arrangements is set forth below under “Legal Ownership of Debt Securities-Global Securities.” The specific terms of the depositary arrangement with respect to any debt securities of a series issued in global form will be described in the prospectus supplement related to such series. We expect that the provisions of the next two paragraphs will apply to all depositary arrangements.

Upon the issuance of a global security, the depositary or its nominee will credit, on its book-entry registration and transfer system, the respective principal amounts of the individual debt securities represented by the global security to the accounts of institutions that have accounts with the depositary. These institutions are called “participants.” The participant accounts to be credited will be designated by the underwriters or agents for such debt securities or by us if the debt securities are offered and sold directly by us. Ownership of beneficial interests in a global security will be limited to participants or persons that may hold interests through participants. Ownership of beneficial interests in a global security will be shown on, and the transfer of that interest will be effected only through, records maintained by the depositary or its nominee, or by participants or persons that own beneficial interests through participants.

Upon receipt of any payment in respect of a global security, the depositary or its nominee will immediately credit participants’ accounts with amounts proportionate to their respective beneficial interests in the principal amount of the global security as shown in the records of the depositary or its nominee. Payments by participants to owners of beneficial interests in a global security held through participants will be governed by standing instructions and customary practices and will be the responsibility of those participants.

Payment and Paying Agents

Unless otherwise indicated in the applicable prospectus supplement, payment of any installment of interest on debt securities will be made to the person in whose name the debt security is registered at the close of business on the security register at the record date for such interest. The principal of (and applicable premium, if any, on) any series of debt securities will be payable at the corporate trust office of the trustee, which initially will be 100 Wall Street, Suite 1600, New York, New York 10005; except that, at our option, payment of interest may be made by check mailed to each holder at the holder’s registered address or by wire transfer of funds to each holder at an account maintained within the United States. (Sections 3.01, 3.07 and 10.02)

If any interest is not punctually paid or provided for on any interest payment date, then interest will stop being payable to the holder on the relevant regular record date and may be paid to the person in whose name the debt security is registered at the close of business on a special record date for the payment of such defaulted interest. A special record date will be fixed by the trustee, which date shall be not more than 15 days and not less than ten days prior to the proposed payment date. Notice of the proposed payment of default interest and the special record date will be given to the holder of the debt security not less than ten days prior to such special record date. In addition, defaulted interest may be paid at any time in any other lawful manner, as described in the indenture. (Section 3.07)

We may appoint one or more paying agents to effect payments in respect of the debt securities. We will identify any paying agent for a series of debt securities in the applicable prospectus supplement. We may terminate the appointment of any paying agent at any time, except that, unless otherwise indicated in the applicable prospectus supplement, we will maintain at least one paying agent in New York City for payments with respect to the debt securities of any series payable in U.S. dollars. (Section 10.02)

Any money deposited with the trustee or a paying agent in respect of any debt security that remains unclaimed at the end of two years (or such shorter period of time for return of such money to PotashCorp under applicable abandoned property laws) after the relevant amounts shall have become due and payable will be repaid to us upon our request. Holders of these debt securities can thereafter look only to us for payment of these amounts. (Section 10.03)

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Merger, Consolidation or Sale

Under the indenture we may amalgamate or consolidate with, or sell, lease or convey all or substantially all of our assets to, or merge with or into any other entity, provided that:

Certain Covenants

Additional Amounts

Payments made by us under or with respect to the debt securities will be free and clear of, and without withholding or deduction for or on account of, any present or future tax, duty, levy, impost, assessment or other governmental charge of any nature whatsoever imposed or levied by or on behalf of the Government of Canada or of any province or territory of Canada or by any authority or agency therein or thereof having power to tax, which we refer to as Taxes, unless we are required to withhold or deduct Taxes by law.

If we are required to withhold or deduct any amount for or on account of Taxes from any payment made with respect to the debt securities, we will pay such additional amounts as may be necessary so that the net amount received by each holder (including additional amounts) after such withholding or deduction will not be less than the amount the holder would have received if the Taxes had not been withheld or deducted; provided that no additional amounts will be payable with respect to certain Taxes specified in the indenture, which we refer to as Excluded Taxes. Excluded Taxes include Taxes:

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We will also make such withholding or deduction and remit the full amount deducted or withheld to the relevant authority in accordance with applicable law.

We will furnish to the holders of the debt securities certified copies of tax receipts evidencing payment by us within 30 days after the date the payment of any Taxes is due.

At least 30 days prior to each date on which any payment under or with respect to the debt securities is due and payable, if we are obligated to pay additional amounts with respect to such payment, we will deliver to the trustee an officer’s certificate stating the fact that such additional amounts will be payable, the amounts payable and such other information necessary to enable the trustee to pay such additional amounts to holders on the payment date. Wherever in this prospectus or a related prospectus supplement we mention the payment of the principal of (or premium, if any) or interest on or any other amount payable under, or in respect of, any debt security of any series, we include the payment of additional amounts to the extent that, in such context, additional amounts are, were or would be payable.

Our obligation to pay additional amounts if and when due will survive the termination of the indenture and the payment of all amounts under or with respect to the debt securities. (Section 10.06)

Limitation on Liens

We may not, and we may not permit any of our subsidiaries to, incur any lien on or with respect to any of our or any of our subsidiaries’ principal property (as this term is defined below) owned on or acquired after the date of the indenture to secure debt without making (or causing such subsidiary to make) effective provision for securing the debt securities equally and ratably with such debt as to such principal property for as long as such debt is so secured. If such debt is subordinate to the debt securities, we must secure the debt securities as to such principal property prior to such debt for so long as such debt is so secured.

The restrictions on liens will not apply to:

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In addition, we and our subsidiaries may incur a lien or liens to secure debt (excluding debt secured by liens permitted under the exceptions listed above) the aggregate amount of which, including attributable debt in respect of sale and leaseback transactions, does not exceed 15% of our consolidated net tangible assets, as such term is defined in the indenture. We and our subsidiaries may also incur a lien or liens to secure any debt incurred pursuant to a sale and leaseback transaction, without securing the debt securities equally and ratably with or prior to such debt, provided that such sale and leaseback transaction is permitted by the provisions of the indenture described below under “—Limitation on Sale and Leaseback Transactions.” (Section 10.07)

For purposes of the limitation on liens covenant and the limitation on sale and leaseback transactions covenant, which is described below, the term “principal property” means any real property interest that is held by us or any of our subsidiaries and that has a gross book value (without deduction of any reserve for depreciation) exceeding 5% of our consolidated net tangible assets (other than any interest that our board of directors determines is not material to the business of PotashCorp and our subsidiaries, taken as a whole), or any of the capital stock or debt securities issued by any of our significant subsidiaries, as such term is defined in the indenture.

Limitation on Sale and Leaseback Transactions

We may not, and we may not permit any of our subsidiaries to, enter into any sale and leaseback transaction with respect to any principal property (except for a period, including renewals, not exceeding 36 months) unless:

Notwithstanding the foregoing, in no event will we be required to defease or retire, in the aggregate with respect to any and all such sale and leaseback transactions, more than 25% of the original aggregate principal amount of a series of debt securities on or prior to the fifth anniversary of the original issue date thereof. If the aggregate net proceeds that we would be otherwise required to use to defease or retire debt securities on or prior

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to the fifth anniversary of the issue date would exceed 25% of the original aggregate principal amount of such series (such excess we refer to as the 25% excess proceeds), then promptly after such fifth anniversary we will defease or retire debt securities in an amount equal to the 25% excess proceeds. Pending such defeasing or retiring of debt securities, the 25% excess proceeds will be invested and maintained by us and for our benefit in permitted short-term investments, and we will not distribute such proceeds in respect of our common shares. (Section 10.08)

For purposes of the limitation on sale and leaseback transactions covenant, the term “attributable debt” means, with respect to any sale and leaseback transaction, the present value (discounted at the rate of interest implicit in the terms of the lease) of the obligations of the lessee under the lease for net rental payments during the remaining term of the lease (including any period for which such lease has been extended). For this purpose, “net rental payments” under any lease for any period means the sum of the rental and other payments required to be paid in the period by the lessee, not including, however, any amounts required to be paid by the lessee (whether or not designated as rental or additional rental) on account of maintenance and repairs, insurance, taxes, assessments or similar charges.

Events of Default, Notice and Waiver

The indenture provides that the following events are events of default with respect to any series of debt securities issued pursuant to the indenture:

An event of default with respect to a particular series of debt securities will not necessarily constitute an event of default with respect to any other series of debt securities.

We are required to file with the trustee annual officers’ certificates as to the absence of specified defaults under the indenture. (Section 10.05)

If an event of default with respect to a series of debt securities occurs and is continuing, the trustee will, at the request of holders of not less than 25% in principal amount of the then-outstanding debt securities of the

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relevant series, declare the principal of, and premium, if any, on, all debt securities of the series to be due and payable, together with accrued interest. The indenture provides that, in certain cases, the holders of a majority in principal amount of the then-outstanding debt securities of a series may on behalf of the holders of all debt securities of that series waive any past default or event of default and rescind and annul any declaration of acceleration and its consequences. (Section 5.02)

The trustee may require indemnification from the holders of debt securities of a series before proceeding to exercise any right or power under the indenture at the request of those holders. (Sections 6.01 and 6.03) The holders of a majority in principal amount of the then-outstanding debt securities of any series may:

However, the trustee may refuse to follow any direction that conflicts with law or the indenture, might involve it in personal liability or is unduly prejudicial to the rights of other holders. (Section 5.12)

No holder will be entitled to pursue any remedy with respect to the indenture unless the trustee fails to act for 60 days after it is given:

and during this 60-day period the holders of a majority in principal amount of all of the then-outstanding debt securities of the applicable series issued under the indenture (treated as a single class) do not give a direction to the trustee that is inconsistent with the enforcement request. (Section 5.07) These provisions will not prevent any holder of debt securities from enforcing payment of the principal of (and premium, if any) and interest on the debt securities on the relevant due dates or redemption date. (Section 5.08)

If an event of default with respect to a series of debt securities occurs and is continuing, the trustee will mail to the holders of those debt securities a notice of the event of default within 90 days after it occurs. However, except in the case of a default in any payment in respect of a series of debt securities, the trustee shall be protected in withholding notice of an event of default if and so long as it determines in good faith that this is in the interests of the holders of the relevant debt securities. (Section 6.02)

Modification of the Indenture

The indenture provides that, in general, we and the trustee may modify the indenture or the rights of the holders of any debt securities issued pursuant to the indenture so long as we obtain the consent of the holders of not less than a majority in principal amount of the then-outstanding debt securities affected by the modification. The indenture also provides, however, that we may not effect any modification without the consent of each affected holder if that modification would, among other things:

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We and the trustee are permitted to enter into one or more supplemental indentures without the consent of any holder of debt securities issued pursuant to the indenture for any of the following purposes:

The indenture contains provisions for convening meetings of the holders of debt securities of a series. (Section 15.01) A meeting may be called at any time by the trustee, and also, upon request to the trustee, by us or by the holders of at least 10% in principal amount of the outstanding debt securities of such series, in any such case upon notice given as provided in the indenture. (Section 15.02) Except for any consent that must be given by the holder of each debt security affected by certain modifications and amendments of the indenture, any resolution presented at a meeting at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding debt securities of that series. (Section 15.04)

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Any resolution passed or decision taken at any meeting of holders of debt securities of any series duly held in accordance with the indenture will be binding on all holders of debt securities of that series whether or not present or represented at the meeting. The quorum at any meeting of the holders of debt securities of a series called to adopt a resolution, and at any reconvened meeting, will be persons holding or representing a majority in principal amount of the outstanding debt securities of a series. (Section 15.04)

Discharge, Defeasance and Covenant Defeasance

We are permitted under the indenture to discharge certain obligations to holders of debt securities that have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the trustee, in trust, funds in an amount sufficient to pay the entire indebtedness on such debt securities in respect of principal (and premium, if any) and interest to the date of such deposit (if such debt securities have become due and payable) or to the stated maturity and redemption date, as the case may be. (Section 4.01)

The indenture provides that we may elect either:

in either case upon the irrevocable deposit by us with the trustee, in trust, of an amount, in the currency in which those debt securities are payable at stated maturity, or government obligations, or both, applicable to those debt securities that through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of (and premium, if any) and interest on those debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates. (Section 14.04)

Such a trust will only be permitted to be established if, among other things, we have delivered to the trustee an opinion of counsel to the effect that the holders of such debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of such defeasance or covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the defeasance or covenant defeasance had not occurred, and such opinion of counsel, in the case of defeasance, will be required to refer to and be based upon a ruling of the Internal Revenue Service or a change in applicable U.S. federal income tax law occurring after the date of the indenture. (Section 14.04)

Governing Law

The indenture and the debt securities will be governed by the laws of the State of New York. (Section 1.12)

Concerning the Trustee

U.S. Bank National Association, as successor trustee, is the trustee under the indenture. An affiliate of the trustee is a lender to us under our $3,500.0 million credit facility. The trustee and its affiliates may also maintain other normal banking relationships, including the maintenance of depositary accounts, with us and certain of our subsidiaries.

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LEGAL OWNERSHIP OF DEBT SECURITIES

“Street Name” and Other Indirect Holders

We generally will not recognize investors who hold debt securities in accounts at banks or brokers as legal holders of those debt securities. This is called holding in “street name.” Instead, we recognize only the bank or broker or the financial institution the bank or broker uses to hold the debt securities. These intermediary banks, brokers and other financial institutions pass along principal, interest and other payments on the debt securities, either because they agree to do so in their customer agreements or because they are legally required to do so. If you hold debt securities in street name, you should check with your own institution to find out:

Registered Holders

Our obligations, as well as the obligations of the trustee and any third parties employed by us or the trustee, run only to persons who are registered as holders of debt securities issued pursuant to the indenture. As noted above, we do not have obligations to you if you hold in street name or through other indirect means, either because you choose to hold debt securities in that manner or because the debt securities are issued in the form of global securities as described below. For example, once we make payment to the registered holder, we have no further responsibility for the payment even if that holder is legally required to pass the payment along to you as a street name customer but does not do so.

Global Securities

A global security is a special type of indirectly held security. If we choose to issue debt securities in the form of one or more global securities, the ultimate beneficial owners of the debt securities will be indirect holders. We do this by requiring that the global security be registered in the name of a financial institution we select and by requiring that the debt securities represented by the global security not be registered in the name of any other holder except in the special situations described below. The financial institution that acts as the sole registered holder of the global security is called the depositary. Any person wishing to own a debt security may do so indirectly through an account with a broker, bank or other financial institution that in turn has an account with the depositary. The prospectus supplement will indicate whether your series of debt securities will be issued only as global securities.

Transfers of debt securities represented by the global security will be made only on the records of the depositary or its nominee by transferring such debt securities from the account of one broker, bank or financial institution to the account of another broker, bank or financial institution. These transfers are made electronically only and are also known as book-entry transfers. Securities in global form are sometimes also referred to as being in book-entry form.

As an indirect holder, your rights relating to a global security will be governed by the account rules of your financial institution and of the depositary, as well as general laws relating to securities transfers. We will not

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recognize you as a holder of debt securities and instead will deal only with the depositary that holds the global security.

You should be aware that if debt securities are issued only in the form of a global security:

In a few special situations described below, the global security will terminate and the indirect interests in it will be exchanged for registered debt securities represented by physical certificates. After that exchange, the choice of whether to hold debt securities in registered form or in street name will be up to you. You must consult your bank or broker to find out how to have your interests in debt securities transferred to your name, so that you will be a registered holder.

Unless we specify otherwise in the prospectus supplement, the special situations for termination of a global security are:

The prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of debt securities covered by the applicable prospectus supplement. When a global security terminates, the depositary (and not us or the trustee) is responsible for deciding the names of the institutions that will be the initial registered holders.

The Term “Holder” as Used in this Prospectus and Elsewhere

In the descriptions of the debt securities included in this prospectus and any prospectus supplement, when we refer to the “holder” of a given debt security as being entitled to certain rights or payments, or being permitted to take certain actions, we are in all cases referring to the registered holder of the debt security.

While you would be the registered holder if you held a certificated security registered in your name, it is likely that the holder will actually be either the broker, bank or other financial institution where you have your street name account, or, in the case of a global security, the depositary. If you are an indirect holder, you will need to coordinate with the institution through which you hold your interest in a debt security in order to determine how the provisions involving holders described in this prospectus and any related prospectus

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supplement will actually apply to you. For example, if the debt security in which you hold a beneficial interest in street name can be repaid at the option of the holder, you cannot exercise the option yourself by following the procedures described in the prospectus supplement. Instead, you would need to cause the institution through which you hold your interest to take those actions on your behalf. Your institution may have procedures and deadlines different from or additional to those described in the prospectus supplement relating to the debt security.

INCOME TAX CONSIDERATIONS

The applicable prospectus supplement will describe the principal U.S. federal income tax consequences and the principal Canadian federal income tax consequences to holders who are residents of the United States of the acquisition, ownership and disposition of the applicable series of debt securities under the U.S. Internal Revenue Code of 1986, as amended, and the Income Tax Act (Canada).