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TABLE OF CONTENTS
TABLE OF CONTENTS

Table of Contents

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-176308


CALCULATION OF REGISTRATION FEE

 
Title of Each
Class of Securities
to be Registered

  Amount
to be
Registered

  Proposed
Maximum
Offering Price
Per Unit

  Proposed
Maximum
Aggregate
Offering Price

  Amount of
Registration
Fee(1)

 
1.750% Senior Notes due 2017   $1,250,000,000   99.046%   $1,238,075,000   $143,741
 
3.125% Senior Notes due 2022   $900,000,000   98.093%   $882,837,000   $102,497
 
  Total           $2,120,912,000   $246,238
 
(1)
Calculated in accordance with Rule 456(b) and Rule 457(r) under the Securities Act of 1933.

Prospectus Supplement
(To Prospectus dated August 15, 2011)

LOGO

$1,250,000,000 1.750% Senior Notes due 2017

$900,000,000 3.125% Senior Notes due 2022



        We are offering $1,250,000,000 aggregate principal amount of our 1.750% senior notes due 2017 and $900,000,000 aggregate principal amount of our 3.125% senior notes due 2022.

        In this prospectus supplement, we refer to the 1.750% senior notes due 2017 as the "2017 notes" and the 3.125% senior notes due 2022 as the "2022 notes" and the 2017 notes and the 2022 notes together as the "notes". We will pay interest on the notes of each series on February 15 and August 15 of each year, beginning February 15, 2012. The 2017 notes will mature on February 15, 2017 and the 2022 notes will mature on February 15, 2022. We may redeem some or all of the notes of either series at our option at any time and from time to time at the redemption prices described under "Description of the Notes—Optional Redemption" in this prospectus supplement.

        The notes will be our unsecured senior obligations and will rank equally in right of payment with all of our other unsecured senior indebtedness from time to time outstanding. The notes will be issued only in denominations of $2,000 and integral multiples of $1,000 in excess thereof. The notes will not be listed on any securities exchange.

        Investing in the notes involves risks. Please read "Risk Factors" beginning on page S-1 of this prospectus supplement and in our Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated by reference into this prospectus supplement and the accompanying prospectus.

 
  Public Offering
Price(1)
  Underwriting
Discount
  Proceeds,
Before Expenses,
to Us
 

Per 2017 Note

    99.046 %   0.350 %   98.696 %

Total for 2017 Notes

  $ 1,238,075,000   $ 4,375,000   $ 1,233,700,000  

Per 2022 Note

    98.093 %   0.450 %   97.643 %

Total for 2022 Notes

  $ 882,837,000   $ 4,050,000   $ 878,787,000  

(1)
Plus accrued interest, if any, from August 18, 2011.

        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

        The notes will be delivered to investors on or about August 18, 2011 in book-entry form only through the facilities of The Depository Trust Company for the accounts of its participants, which may include Clearstream Banking, société anonyme, and Euroclear Bank S.A./N.V., against payment in New York, New York.



Joint Book-Running Managers

Barclays Capital   Citigroup   J.P. Morgan

BofA Merrill Lynch   Wells Fargo Securities



Mitsubishi UFJ Securities   RBS   SOCIETE GENERALE   BNP PARIBAS
BNY Mellon Capital Markets, LLC   Credit Suisse   Scotia Capital   UBS Investment Bank
BBVA   Mizuho Securities   Banca IMI   Standard Chartered Bank



August 15, 2011


Table of Contents


TABLE OF CONTENTS

 
  Page

Prospectus Supplement

About This Prospectus Supplement

 
i

Risk Factors

  S-1

Occidental

  S-3

Use of Proceeds

  S-3

Description of the Notes

  S-4

Certain United States Federal Income Tax Consequences To Non-U.S. Holders

  S-11

Underwriting

  S-13

Legal Matters

  S-16

Where You Can Find More Information

  S-16

Prospectus

About This Prospectus

 
i

Risk Factors

  1

Forward-Looking Statements

  1

Where You Can Find More Information

  2

Occidental

  3

Use of Proceeds

  4

Description of Senior Debt Securities

  4

Plan of Distribution

  17

Legal Matters

  18

Experts

  18




ABOUT THIS PROSPECTUS SUPPLEMENT

        No action has been or will be taken in any jurisdiction by us or by any underwriter that would permit a public offering of the notes or the possession or distribution of this prospectus supplement, the accompanying prospectus or any related free writing prospectus in any jurisdiction where action for that purpose is required, other than the United States. Unless otherwise expressly stated or the context otherwise requires, references to "dollars," "$" and other similar references in this prospectus supplement, the accompanying prospectus and any related free writing prospectuses are to U.S. dollars.

        No person is authorized to give any information or to make any representations other than those contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or any free writing prospectus we may provide to you in connection with this offering and, if given or made, such information or representations must not be relied upon as having been authorized. This prospectus supplement, the accompanying prospectus and any such free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in this prospectus supplement or an offer to sell or the solicitation of an offer to buy those securities in any circumstances or jurisdiction in which such offer or solicitation is unlawful.

        Unless otherwise expressly stated or the context otherwise requires, the words "Occidental," "we," "us" and "our" as used in this prospectus supplement refer only to Occidental Petroleum Corporation and not to any of its subsidiaries.

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RISK FACTORS

        Investing in the notes involves risks. You should carefully consider the following risk factors, in addition to the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. Specifically, please see "Risk Factors" included in our Annual Report on Form 10-K for the year ended December 31, 2010 and the other information in that and the other reports that we file with the Securities and Exchange Commission, or SEC, that are incorporated by reference in this prospectus supplement for a discussion of risk factors that may affect our business. Realization of any of those risks or the following risks or adverse results from any matter listed under the heading "Forward-Looking Statements" in the accompanying prospectus or in any such reports could have a material adverse effect on our business, financial condition, cash flows and results of operations, and you might lose all or part of your investment.

Risks Related to the Notes

The notes will be effectively subordinated to the indebtedness and other liabilities of our subsidiaries.

        Substantially all of our operations are conducted through our subsidiaries. None of our subsidiaries is a guarantor of the notes. As a result, our right to receive assets upon the liquidation or recapitalization of any of our subsidiaries, and your consequent right to benefit from our receipt of those assets, will be subject to the claims of such subsidiary's creditors. Accordingly, the notes are effectively subordinated to all indebtedness and other liabilities, including trade payables, of our subsidiaries. Even if we were recognized as a creditor of one or more of our subsidiaries, our claims would still be effectively subordinated to any security interests in or other liens on the assets of any such subsidiary and to any indebtedness or other liabilities of any such subsidiary senior to our claims.

        In addition, we derive substantially all of our revenues from our subsidiaries. As a result, our cash flow and our ability to service our debt and other obligations, including the notes, will depend on the results of operations of our subsidiaries and upon the ability of our subsidiaries to provide us with cash to pay amounts due on our obligations, including the notes. Our subsidiaries are separate and distinct legal entities and have no obligation to make payments on the notes or to make funds available to us for that purpose. In addition, dividends, loans or other distributions from our subsidiaries to us may be subject to contractual and other restrictions, are dependent upon results of operations of our subsidiaries, may be subject to tax or other laws limiting our ability to repatriate funds from foreign subsidiaries and may be subject to other business considerations.

The notes will be unsecured and therefore will be effectively subordinated to any secured indebtedness we may incur.

        The notes will not be secured by any of our assets. As a result, the notes will be effectively subordinated to any secured debt we or our subsidiaries may incur in the future to the extent of the value of the assets securing such debt. In any liquidation, dissolution, bankruptcy or other similar proceeding, the holders of any of our secured debt and the secured debt of our subsidiaries may assert rights against the assets pledged to secure that debt in order to receive full payment of their debt before the assets may be used to pay other creditors, including the holders of the notes.

Our credit ratings may not reflect all risks of an investment in the notes and there is no protection in the indenture for holders of the notes in the event of a ratings downgrade.

        Our credit ratings are an assessment by rating agencies of our ability to pay our debts when due but they may not reflect the potential impact of all risks related to an investment in the notes. Consequently, real or anticipated changes in our credit ratings will generally affect the market value of the notes. Credit ratings are not a recommendation to buy, sell or hold any security, and may be revised or withdrawn at any time by the issuing organization in its sole discretion. We have no

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obligation to maintain the ratings and neither we nor any underwriter undertakes any obligation to advise holders of notes of any change in ratings. Each agency's rating should be evaluated independently of any other agency's rating.

The indenture does not limit the amount of indebtedness that we or our subsidiaries may incur.

        The indenture does not limit our ability or that of our subsidiaries to incur additional indebtedness or contain provisions that would afford holders of the notes protection in the event of a decline in our credit quality or a take-over, recapitalization or highly leveraged or similar transaction. Accordingly, we and our subsidiaries could, in the future, enter into transactions that could increase the amount of indebtedness outstanding at that time or otherwise adversely affect your position in our consolidated capital structure or our credit ratings.

If an active trading market does not develop for the notes, you may be unable to sell your notes or to sell your notes at a price that you deem sufficient.

        The notes are a new issue of securities with no established trading market, and we do not intend to list them on any securities exchange or automated quotation system. As a result, an active trading market for the notes may not develop, or if one does develop, it may not be sustained. If an active trading market fails to develop or cannot be sustained, you may not be able to resell your notes at their fair market value or at all.

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OCCIDENTAL

        Our principal businesses consist of three segments operated by our subsidiaries and affiliates. The oil and gas segment explores for, develops, produces and markets crude oil, including natural gas liquids (NGLs) and condensate (together with NGLs, "liquids"), as well as natural gas. The chemical segment manufactures and markets basic chemicals, vinyls and other chemicals. The midstream, marketing and other segment gathers, treats, processes, transports, stores, purchases and markets crude oil, liquids, natural gas, carbon dioxide and power. It also trades around its assets, including pipelines and storage capacity, and trades oil and gas, other commodities and commodity-related securities. Our principal executive offices are located at 10889 Wilshire Boulevard, Los Angeles, California 90024, telephone (310) 208-8800.


USE OF PROCEEDS

        The net proceeds from this offering are expected to be approximately $2,110 million, after deducting the underwriting discounts and our estimated offering expenses. We intend to use the net proceeds from the sale of the notes for general corporate purposes, which may include ordinary course working capital increases, acquisitions, retirement of debt, stock repurchases and other business opportunities.

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DESCRIPTION OF THE NOTES

        The 2017 and the 2022 notes will each constitute a separate series of senior debt securities under an indenture (the "indenture") to be entered into between us and The Bank of New York Mellon Trust Company, N.A., as trustee. We will issue the notes under an officers' certificate pursuant to such indenture setting forth the specific terms applicable to such notes. References to the "indenture" in this description mean such indenture as so supplemented by such certificate.

        The following description is a summary of some of the provisions of the notes and the indenture. This summary is not complete and is qualified in its entirety by reference to the indenture. You should carefully read the summary below, the description of the general terms and provisions of our senior debt securities set forth in the accompanying prospectus under the heading "Description of Senior Debt Securities" and the indenture before investing in the notes.

        This description of the notes supplements and, to the extent it is inconsistent, replaces the description of the general provisions of the senior debt securities and the indenture in the accompanying prospectus. The notes are "senior debt securities" as that term is used in the accompanying prospectus, the indenture is referred to in the accompanying prospectus as the "Senior Indenture" and the trustee is referred to in the accompanying prospectus as the "Senior Indenture Trustee." In this description, the term "Securities" refers to all senior debt securities that may be issued under the indenture and includes the notes.

Description of the Notes

        The notes are unsecured and will rank equally in right of payment with all of our other senior unsecured indebtedness. The indenture does not limit the aggregate principal amount of Securities that we may issue under the indenture and we may, without the consent of holders of outstanding Securities, issue additional Securities thereunder. In addition, the indenture does not limit the amount of other unsecured debt that we or our subsidiaries may issue or incur. Such other unsecured debt may have different terms than the notes. Our previously issued and outstanding senior debt does have different terms than the notes (including different restrictive covenants and event of default provisions). The terms of the notes will only be as described in the indenture, the accompanying prospectus and this prospectus supplement. As of June 30, 2011, we had approximately $4.3 billion of senior debt securities outstanding which ranked equally in right of payment with the notes.

        Substantially all of our operations are conducted through our subsidiaries. None of our subsidiaries is a guarantor of the notes. As a result, our right to receive assets upon the liquidation or recapitalization of any of our subsidiaries, and your consequent right to benefit from our receipt of those assets, will be subject to the claims of such subsidiary's creditors. Accordingly, the notes are effectively subordinated to all indebtedness and other liabilities, including trade payables, of our subsidiaries. Even if we were recognized as a creditor of one or more of our subsidiaries, our claims would still be effectively subordinated to any security interests in or other liens on the assets of any such subsidiary and to any indebtedness or other liabilities of any such subsidiary senior to our claims.

Principal, Maturity and Interest

        The 2017 notes will be initially limited to $1,250,000,000 aggregate principal amount, and the 2022 notes will be initially limited to $900,000,000 aggregate principal amount. The 2017 notes will mature on February 15, 2017 and the 2022 notes will mature on February 15, 2022. We may, from time to time, without the consent of the holders of the notes of any series, reopen the 2017 notes or the 2022 notes or both and issue additional notes of such series.

        Interest on the 2017 notes will accrue at the rate of 1.750% per year, and interest on the 2022 notes will accrue at the rate of 3.125% per year. Interest on the notes will be payable semi-annually in

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arrears on February 15 and August 15, commencing on February 15, 2012. We will make each interest payment to the holders of record of the notes at the close of business on the immediately preceding February 1 and August 1, respectively.

        If any interest payment date, maturity date or redemption date for the 2017 notes or the 2022 notes falls on a day that is not a business day, the payment will be made on the next business day, and no interest will accrue on that payment for the period from and after such interest payment date, maturity date or redemption date until such following business day.

        Interest on the 2017 notes and the 2022 notes will accrue from August 18, 2011 and will be computed on the basis of a 360-day year comprised of twelve 30-day months.

        Interest payable on any interest payment date or on the maturity date of the 2017 notes or the 2022 notes shall be the amount of interest accrued from, and including, the immediately preceding interest payment date in respect of which interest has been paid or duly provided for on the notes of such series (or from and including the original issue date of the notes of such series, if no interest has been paid or duly provided for on the notes of such series) to, but not including, such interest payment date or maturity date, as the case may be.

Place of Payment, Transfer and Exchange

        All payments on the notes will be made, and transfers of the notes will be registrable, at the trustee's office in The City of New York, unless we designate another place for such purpose.

Optional Redemption

        The 2017 notes are redeemable at our option, in whole at any time or in part from time to time, and the 2022 notes are redeemable at our option, in whole at any time or in part from time to time prior to November 15, 2021, at a redemption price equal to the greater of:

plus, in each case, accrued and unpaid interest on the principal amount of the notes of such series being redeemed to the redemption date.

        On and after November 15, 2021, the 2022 notes are redeemable at our option, in whole at any time or in part from time to time, at a redemption price equal to 100% of the principal amount of the 2022 notes to be redeemed, plus accrued and unpaid interest on the principal amount of the 2022 notes being redeemed to the redemption date.

        Notwithstanding the foregoing, with respect to payments of interest on the 2017 notes or the 2022 notes that are due and payable on any interest payment dates falling on or prior to a redemption date for the notes of such series, we will make such payments to the record holders of such notes at the close of business on the relevant regular record dates.

        We will send to each holder of the 2017 notes or the 2022 notes, as applicable, notice of any redemption of notes of such series at least 30 days but not more than 60 days before the applicable redemption date. Unless we default in payment of the redemption price (or accrued and unpaid interest) with respect to the notes to be redeemed, no interest will accrue on the notes or portions

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thereof so redeemed for the period on and after such redemption date. If less than all of the notes of such series are to be redeemed, the trustee will select the notes (or portions thereof) to be redeemed by such method as the trustee deems fair and appropriate.

        "Adjusted Treasury Rate" means, with respect to any redemption date for the 2017 notes or the 2022 notes, as applicable, the rate per year equal to the semi-annual equivalent yield to maturity 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 such redemption date.

        "Comparable Treasury Issue" means, with respect to any redemption date for the 2017 notes or the 2022 notes, as applicable, the United States Treasury security selected by the Quotation Agent as having a maturity comparable to the remaining term of the notes of such series to be redeemed 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 of such series.

        "Comparable Treasury Price" means, with respect to any redemption date for the 2017 notes or the 2022 notes, as applicable, (1) the average of the Reference Treasury Dealer Quotations for such redemption date, after excluding the highest and lowest Reference Treasury Dealer Quotations, or (2) if the trustee obtains fewer than three Reference Treasury Dealer Quotations, the average of all such Reference Treasury Dealer Quotations, such average in any case to be determined by the Quotation Agent, or (3) if only one Reference Treasury Dealer Quotation is received, such Reference Treasury Dealer Quotation.

        "Quotation Agent" means, with respect to any redemption date for the 2017 notes or the 2022 notes, as applicable, the Reference Treasury Dealer appointed by us.

        "Reference Treasury Dealer" means, with respect to any redemption date for the 2017 notes or the 2022 notes, as applicable, (1) Barclays Capital Inc., Citigroup Global Markets Inc. and J.P. Morgan Securities LLC (or their respective affiliates which are primary U.S. Government securities dealers) and their respective successors; provided, however, that if any of them shall cease to be a primary U.S. Government securities dealer in the United States of America (a "Primary Treasury Dealer"), we will substitute for it another Primary Treasury Dealer and (2) any other Primary Treasury Dealer or Dealers selected by us.

        "Reference Treasury Dealer Quotations" means, with respect to each Reference Treasury Dealer and any redemption date for the 2017 notes or the 2022 notes, as applicable, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the trustee by such Reference Treasury Dealer at 5:00 p.m. on the third business day in The City of New York preceding such redemption date.

Discharge

        We may terminate at any time our obligations under the indenture with respect to either or both series of notes (other than certain limited obligations, such as the obligation to transfer and exchange the notes of that series) by (1)(a) delivering all of the notes of that series to the trustee to be cancelled or (b) depositing with the trustee in trust funds or non-callable United States government or government-guaranteed obligations sufficient without reinvestment to pay all remaining principal and interest on the notes of that series and (2) complying with certain other provisions of the indenture.

        If we elect to discharge our obligations with respect to either or both series of notes by depositing cash or United States government or government guaranteed obligations as described above, under present law such discharge is likely to be treated for United States federal income tax purposes as a redemption of notes of that series prior to maturity in exchange for the property deposited in trust. In

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that event, each holder would generally recognize, at the time of discharge, gain or loss for United States federal income tax purposes measured by the difference between (1) the sum of (a) the amount of any cash and (b) the fair market value of any property deposited in trust deemed received by such holder (unless attributable to accrued interest) and (2) such holder's tax basis in the notes of that series deemed surrendered. After the discharge, each such holder would likely be treated as if it held an undivided interest in the cash (or investments made therewith) and the property held in trust (or investments made with interest received therefrom). Each such holder would generally be subject to tax liability in respect of interest income and original issue discount, if applicable, thereon and would recognize any gain or loss upon any disposition, including redemption, of the assets held in trust. Although tax might be owed, the holder of a discharged note would not receive cash (except for current payments of interest on that note) until the maturity or earlier redemption (or, if applicable, repurchase by us at the option of the holder) of that note. United States federal income tax treatment of this nature could affect the purchase price that a holder would receive upon the sale of the notes. You are urged to consult with your tax advisor regarding the tax consequences of the discharge of our obligations.

Book-Entry; Delivery and Form

        The notes will be issued in the form of one or more global notes ("Global Notes") which will be held by the trustee as custodian for The Depository Trust Company (the "Depositary"), New York, New York, and registered in the name of Cede & Co., as nominee of the Depositary. All interests in the Global Notes will be subject to the operations and procedures of the Depositary, Euroclear Bank S.A./N.V. ("Euroclear") and Clearstream Banking, société anonyme ("Clearstream, Luxembourg"). The notes will be issued in fully registered form without coupons and will be issued in, and beneficial interests in the Global Notes must be held in, minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

        Notwithstanding the foregoing, if (1) the Depositary notifies us that it is unwilling or unable to continue as depositary for the notes of any series or if the Depositary ceases to be eligible to act in such capacity and a successor depositary is not appointed by us within 90 days, (2) an event or default (as defined in the indenture) with respect to the notes of any series shall have occurred and be continuing or (3) we in our sole discretion shall determine that the notes of any series will no longer be represented by Global Notes, the Global Notes of such series will be exchanged for notes of such series in definitive form of like tenor and in an equal aggregate principal amount in authorized denominations. Such definitive notes will be registered in such name or names as the Depositary instructs the trustee.

        The Depositary has advised us that pursuant to procedures established by it (i) upon the issuance of the Global Notes, the Depositary or its custodian will credit, on its internal system, the principal amount of the individual beneficial interests represented by such Global Notes to the respective accounts of persons who have accounts with such Depositary and (ii) ownership of beneficial interests in the Global Notes will be shown on, and the transfer of such ownership will be effected only through, records maintained by the Depositary or its nominee (with respect to interests of participants) and the records of participants (with respect to interests of persons other than participants). Ownership of beneficial interests in the Global Notes will be limited to persons who have accounts with the Depositary ("participants") or persons who hold interests through participants. Holders may hold their interests in the Global Notes directly through the Depositary if they are participants in such system, or indirectly through organizations that are participants in such system.

        So long as the Depositary, or its nominee, is the registered owner or holder of the notes, the Depositary or such nominee, as the case may be, will be considered the sole owner or holder of the notes represented by such Global Notes for all purposes under the indenture. No beneficial owner of

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an interest in the Global Notes will be able to transfer that interest except in accordance with the Depositary's procedures and those provided for under the indenture.

        Payments of the principal of and premium, if any, and interest on the Global Notes will be made to the Depositary or its nominee, as the case may be, as the registered owner of the Global Notes. Neither we nor the trustee or any paying agent under the indenture will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the Global Notes or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

        The Depositary has advised us that its present practice is, upon receipt of any payment of principal of and premium, if any, and interest on the Global Notes, to credit participants' accounts immediately with payments in amounts proportionate to their respective beneficial interests in the principal amount of the Global Notes as shown on the records of the Depositary. Payments by participants to owners of beneficial interests in the Global Notes held through such participants will be governed by standing instructions and customary practice, as is now the case with securities held for the accounts of customers registered in the names of nominees for such customers. Such payments will be the responsibility of such participants. Transfers between participants in the Depositary will be effected in the ordinary way through the Depositary's same-day funds settlement system in accordance with the Depositary's rules and will be settled in same-day funds.

        The Depositary has advised us as follows: the Depositary is a limited purpose trust company organized under the laws of the State of New York, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the Uniform Commercial Code and a "clearing agency" registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934. The Depositary was created to hold securities for its participants and facilitate the clearance and settlement of securities transactions between participants through electronic book-entry changes in accounts of its participants, thereby eliminating the need for physical movement of certificates. Participants include securities brokers and dealers, banks, trust companies and clearing corporations and certain other organizations. Indirect access to the Depositary system is available to others such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly, or indirect participants.

        Although the Depositary has agreed to the foregoing procedures in order to facilitate transfers of interests in the Global Notes among participants of the Depositary, it is under no obligation to perform such procedures, and such procedures may be discontinued at any time. None of us, any of the underwriters or the trustee will have any responsibility for the performance by the Depositary or its participants or indirect participants of their respective obligations under the rules and procedures governing their operations.

        Clearstream, Luxembourg and Euroclear hold interests on behalf of their participating organizations through customers' securities accounts in Clearstream, Luxembourg's and Euroclear's names on the books of their respective depositaries, which hold those interests in customers' securities accounts in the depositaries' names on the books of the Depositary. At the present time, Citibank, N.A. acts as U.S. depositary for Clearstream, Luxembourg, and JPMorgan Chase Bank, N.A. acts as U.S. depositary for Euroclear (the "U.S. Depositaries").

        Clearstream, Luxembourg holds securities for its participating organizations ("Clearstream Participants") and facilitates the clearance and settlement of securities transactions between Clearstream Participants through electronic book-entry changes in accounts of Clearstream Participants, thereby eliminating the need for physical movement of certificates. Clearstream, Luxembourg provides to Clearstream Participants, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing.

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        Clearstream, Luxembourg is registered as a bank in Luxembourg, and as such is subject to regulation by the Commission de Surveillance du Secteur Financier and the Banque Centrale du Luxembourg, which supervise and oversee the activities of Luxembourg banks. Clearstream Participants are financial institutions including investment banks, securities brokers and dealers, banks, trust companies and clearing corporations, and may include the underwriters or their affiliates. Indirect access to Clearstream, Luxembourg is available to other institutions that clear through or maintain a custodial relationship with a Clearstream Participant. Clearstream, Luxembourg has established an electronic bridge with Euroclear as the operator of the Euroclear System (the "Euroclear Operator") in Brussels to facilitate settlement of trades between Clearstream, Luxembourg and the Euroclear Operator.

        Distributions with respect to the notes held beneficially through Clearstream, Luxembourg will be credited to cash accounts of Clearstream Participants in accordance with its rules and procedures, to the extent received by the U.S. Depositary for Clearstream, Luxembourg.

        Euroclear holds securities and book-entry interests in securities for participating organizations ("Euroclear Participants") and facilitates the clearance and settlement of securities transactions between Euroclear Participants, and between Euroclear Participants and participants of certain other securities intermediaries through electronic book-entry changes in accounts of such participants or other securities intermediaries. Euroclear provides Euroclear Participants, among other things, with safekeeping, administration, clearance and settlement, securities lending and borrowing, and related services. Euroclear Participants are investment banks, securities brokers and dealers, banks, central banks, supranationals, custodians, investment managers, corporations, trust companies and certain other organizations, and may include the underwriters or their affiliates. Non-participants in Euroclear may hold and transfer beneficial interests in a Global Note through accounts with a participant in the Euroclear System or any other securities intermediary that holds a book-entry interest in a Global Note through one or more securities intermediaries standing between such other securities intermediary and Euroclear.

        Securities clearance accounts and cash accounts with the Euroclear Operator are governed by the Terms and Conditions Governing Use of Euroclear and the related Operating Procedures of the Euroclear System, and applicable Belgian law (collectively, the "Terms and Conditions"). The Terms and Conditions govern transfers of securities and cash within Euroclear, withdrawals of securities and cash from Euroclear and receipts of payments with respect to securities in Euroclear. All securities in Euroclear are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. The Euroclear Operator acts under the Terms and Conditions only on behalf of Euroclear Participants, and has no record of or relationship with persons holding through Euroclear Participants.

        Distributions on the notes held beneficially through Euroclear will be credited to the cash accounts of Euroclear Participants in accordance with the Terms and Conditions, to the extent received by the U.S. Depositary for Euroclear.

        Transfers between Euroclear Participants and Clearstream Participants will be effected in the ordinary way in accordance with their respective rules and operating procedures.

        Cross-market transfers between direct participants in the Depositary, on the one hand, and Euroclear Participants or Clearstream Participants, on the other hand, will be effected through the Depositary in accordance with the Depositary's rules on behalf of Euroclear or Clearstream, Luxembourg, as the case may be, by its U.S. Depositary; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, Luxembourg, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (European time) of such system. Euroclear or Clearstream, Luxembourg, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its U.S. Depositary to

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take action to effect final settlement on its behalf by delivering or receiving interests in the Global Notes in the Depositary, and making or receiving payment in accordance with normal procedures for same-day fund settlement applicable to the Depositary. Euroclear Participants and Clearstream Participants may not deliver instructions directly to their respective U.S. Depositaries.

        Due to time zone differences, the securities accounts of a Euroclear Participant or Clearstream Participant purchasing an interest in a Global Note from a direct participant in the Depositary will be credited, and any such crediting will be reported to the relevant Euroclear Participant or Clearstream Participant, during the securities settlement processing day (which must be a business day for Euroclear or Clearstream, Luxembourg) immediately following the settlement date of the Depositary. Cash received in Euroclear or Clearstream, Luxembourg as a result of sales of interests in a Global Note by or through a Euroclear Participant or Clearstream Participant to a direct participant in the Depositary will be received with value on the settlement date of the Depositary but will be available in the relevant Euroclear or Clearstream, Luxembourg cash account only as of the business day for Euroclear or Clearstream, Luxembourg following the Depositary's settlement date.

        The information in this section concerning the Depositary, Euroclear and Clearstream, Luxembourg and their book-entry systems has been obtained from sources that we believe to be reliable, but we take no responsibility for the accuracy of that information.

        Although Euroclear and Clearstream, Luxembourg have agreed to the foregoing procedures to facilitate transfers of interests in the Global Notes among Euroclear Participants and Clearstream Participants, they are under no obligation to perform or to continue to perform such procedures, and such procedures may be discontinued at any time. None of us, any of the underwriters or the trustee will have any responsibility for the performance by Euroclear or Clearstream, Luxembourg or their respective Participants of their respective obligations under the rules and procedures governing their operations.

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CERTAIN UNITED STATES FEDERAL INCOME TAX CONSEQUENCES
TO NON-U.S. HOLDERS

        The following is a summary of certain United States federal income tax consequences of the purchase, ownership, and disposition of the notes by an initial purchaser of the notes that, for United States federal income tax purposes, is not a "United States person" as defined below (a "Non-U.S. Holder") and purchases the notes pursuant to this prospectus supplement. This summary is based upon existing United States federal income tax law, which is subject to differing interpretations or change, possibly with retroactive effect. This summary does not discuss all aspects of United States federal income taxation which may be important to particular investors in light of their individual investment circumstances, such as notes held by investors subject to special tax rules (e.g., banks, financial institutions, insurance companies, broker- dealers, partnerships and their partners, and tax-exempt organizations (including private foundations)) or to persons that will hold the notes as part of a straddle, hedge, conversion, constructive sale, or other integrated security transaction for United States federal income tax purposes, all of whom may be subject to tax rules that differ significantly from those summarized below. In addition, this summary does not discuss any (i) United States federal income tax consequences to a Non-U.S. Holder that (A) is engaged in the conduct of a United States trade or business, (B) is a nonresident alien individual and such holder is present in the United States for 183 or more days during the taxable year, or (C) is a corporation which operates through a United States branch, and (ii) state, local or non-United States tax considerations. Each prospective investor is urged to consult its tax advisor regarding the United States federal, state, local, and non-United States income and other tax considerations of the purchase, ownership, and disposition of the notes.

        For the purposes of this summary, a "United States person" is, for United States federal income tax purposes, (i) a citizen or resident of the United States, (ii) a corporation (or other entity classified as a corporation for United States Federal income tax purposes) created or organized in or under the law of, the United States or any State or the District of Columbia, (iii) an estate the income of which is includible in gross income for United States federal income tax purposes regardless of its source, or (iv) a trust (A) the administration of which is subject to the primary supervision of a United States court and which has one or more United States persons who have the authority to control all substantial decisions of the trust or (B) that has otherwise validly elected to be treated as a United States person.

Interest Income

        Payments of interest on the notes made to a Non-U.S. Holder will not be subject to United States federal income or withholding tax provided that (i) such holder (A) does not actually or constructively own 10% or more of the total combined voting power of all classes of our stock entitled to vote and (B) is not a controlled foreign corporation that is related to us through stock ownership for United States federal income tax purposes and (ii) the requirements of section 871(h) or 881(c) of the Internal Revenue Code of 1986, as amended (the "Code"), are satisfied as described below under the heading "Owner's Statement Requirement."

Sale or Exchange

        A Non-U.S. Holder generally will not be subject to United States federal income tax on gain recognized on a sale, exchange, redemption, or other disposition of a note.

Owner's Statement Requirement

        In order to avoid withholding tax on interest under section 871(h) or 881(c) of the Code, either the beneficial owner of a note or a securities clearing organization, bank or other financial institution that holds customers' securities in the ordinary course of its trade or business (a "Financial

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Institution") and that holds a note on behalf of such owner must file a statement with us or our agent to the effect that the beneficial owner is not a United States person. This requirement will be satisfied if we or our agent receives (i) a statement (an "Owner's Statement") from the beneficial owner of a note in which such owner certifies, under penalties of perjury, that such owner is not a United States person and provides such owner's name and address, and if applicable, information with respect to tax treaty benefits, on an Internal Revenue Service Form W-8BEN (or suitable substitute form) or (ii) a statement from the Financial Institution holding the note on behalf of the beneficial owner in which the Financial Institution certifies, under penalties of perjury, that it has received the Owner's Statement, together with a copy of the Owner's Statement. The beneficial owner must inform us or our agent (or, in the case of a statement described in clause (ii) of the immediately preceding sentence, the Financial Institution) within 30 days of any change in information on the Owner's Statement.

Backup Withholding and Information Reporting

        In general, a Non-U.S. Holder will not be subject to backup withholding or information reporting with respect to payments of interest and proceeds from the sale or other disposition of notes, if an Owner's Statement or similar documentation is received or an exemption has otherwise been established, provided that the relevant agent does not know or have reason to know that the payee is a United States person. If a note is held by a Non-U.S. Holder through a United States or United States related broker or financial institution and, in such case, if the Non-U.S. Holder fails to provide an Owner's Statement or other appropriate evidence of non-United States status, backup withholding may apply.

        Backup withholding is not an additional tax. Any amount withheld under the backup withholding rules from a payment to a Non-U.S. Holder may be refunded or credited against the Non-U.S. Holder's United States federal income tax liability if the Non-U.S. Holder provides the required information to the United States Internal Revenue Service.

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UNDERWRITING

        We and the underwriters named below have entered into an underwriting agreement with respect to the notes. Subject to certain conditions, each underwriter has severally agreed to purchase the principal amount of the notes indicated in the following table.

Underwriters
  Principal Amount
of 2017 Notes
  Principal Amount
of 2022 Notes
 

Barclays Capital Inc. 

  $ 187,500,000   $ 135,000,000  

Citigroup Global Markets Inc. 

  $ 187,500,000   $ 135,000,000  

J.P. Morgan Securities LLC

  $ 187,500,000   $ 135,000,000  

Merrill Lynch, Pierce, Fenner & Smith Incorporated

  $ 187,500,000   $ 135,000,000  

Wells Fargo Securities, LLC

  $ 87,500,000   $ 63,000,000  

Mitsubishi UFJ Securities (USA), Inc. 

  $ 62,500,000   $ 45,000,000  

RBS Securities Inc. 

  $ 62,500,000   $ 45,000,000  

SG Americas Securities, LLC

  $ 62,500,000   $ 45,000,000  

BNP Paribas Securities Corp. 

  $ 30,000,000   $ 21,600,000  

BNY Mellon Capital Markets, LLC

  $ 30,000,000   $ 21,600,000  

Credit Suisse Securities (USA) LLC

  $ 30,000,000   $ 21,600,000  

Scotia Capital (USA) Inc. 

  $ 30,000,000   $ 21,600,000  

UBS Securities LLC

  $ 30,000,000   $ 21,600,000  

Banco Bilbao Vizcaya Argentaria, S.A. 

  $ 25,000,000   $ 18,000,000  

Mizuho Securities USA Inc. 

  $ 25,000,000   $ 18,000,000  

Banca IMI S.p.A. 

  $ 12,500,000   $ 9,000,000  

Standard Chartered Bank

  $ 12,500,000   $ 9,000,000  
           
 

Total

  $ 1,250,000,000   $ 900,000,000  
           

        The underwriters are committed, subject to certain conditions, to take and, if any are taken, pay for all of the notes being offered.

        Notes sold by the underwriters to the public will initially be offered at the respective initial public offering prices set forth on the cover of this prospectus supplement. Any notes sold by the underwriters to securities dealers may be sold at a discount from the initial public offering prices of up to 0.200% of the principal amount of the 2017 notes and up to 0.300% of the principal amount of the 2022 notes. Any such securities dealers may resell notes purchased from the underwriters to certain other brokers or dealers at a discount from the initial public offering prices of up to 0.125% of the principal amount of the 2017 notes and up to 0.250% of the principal amount of the 2022 notes. If all the notes of any series are not sold at the initial offering prices, the underwriters may change the offering prices to the public and the other selling terms of the notes of such series. The offering of the notes by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part.

        The following table shows the underwriting discounts that we are to pay to the underwriters in connection with this offering:

 
  Per 2017 Note   Per 2022 Note   Total  

Underwriting discounts

    0.350 %   0.450 % $ 8,425,000  

        The notes of each series are a new issue of securities with no established trading market. We have been advised by the underwriters that the underwriters intend to make a market in each series of notes but they are not obligated to do so and may discontinue market making at any time without notice. No

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assurance can be given as to whether a trading market for any series of notes will develop or as to the liquidity of any trading market for any series of notes that may develop.

        In connection with the offering, the underwriters may purchase and sell notes in the open market. These transactions may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater number of notes than they are required to purchase in the offering. Stabilizing transactions consist of certain bids or purchases made for the purpose of preventing or retarding a decline in the market prices of the notes while the offering is in progress.

        The underwriters also may impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the underwriting syndicate has repurchased notes sold by or for the account of such underwriter in stabilizing or short covering transactions.

        These activities by the underwriters, as well as other purchases by the underwriters for their own accounts, may stabilize, maintain or otherwise affect the market prices of the notes. As a result, the prices of the notes may be higher than the prices that otherwise might exist in the open market. If these activities are commenced, they may be discontinued by the underwriters at any time without notice. These transactions may be effected in the over-the-counter market or otherwise.

        We estimate that our share of the total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $2.5 million.

        We have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933.

        In the ordinary course of their respective businesses, the underwriters and their respective affiliates have engaged, and may in the future engage, in commercial banking and investment banking transactions with us and our affiliates, for which they have received and in the future may receive compensation.

        Banco Bilbao Vizcaya Argentaria, S.A., Banca IMI S.p.A. and Standard Chartered Bank will not effect any offers or sales of any notes in the United States unless it is through one or more U.S. registered broker-dealers as permitted by the regulations of the Financial Industry Regulatory Authority, Inc.

European Economic Area

        In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a Relevant Member State), each underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the Relevant Implementation Date) it has not made and will not make an offer of notes to the public in that Relevant Member State other than:

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        For the purposes of this provision, the expression an "offer of notes to the public" in relation to any notes in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe the notes, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in each Relevant Member State and the expression "2010 PD Amending Directive" means Directive 2010/73/EU.

United Kingdom

        Each underwriter has represented and agreed that:

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LEGAL MATTERS

        Certain legal matters in connection with the offering of the notes will be passed upon for us by Kendrick F. Royer, our Assistant General Counsel. Certain matters relating to federal income tax considerations will be passed upon for us by Skadden, Arps, Slate, Meagher & Flom LLP, Los Angeles, California. Sidley Austin LLP, San Francisco, California, will act as counsel to the underwriters.


WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission, or SEC. You may read and copy any document we file at the SEC's Public Reference Room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the Public Reference Room. The SEC also maintains a website at www.sec.gov that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC, including us. These reports, proxy statements and other information can also be read through the Investor Relations section of our website at www.oxy.com. Information on our website does not constitute part of, and is not incorporated by reference in, this prospectus supplement or the accompanying prospectus and should not be relied upon in connection with making any investment decision with respect to the notes.

        The SEC allows us to "incorporate by reference" the information that we file with the SEC. This permits us to disclose important information to you by referencing these filed documents. Any information referenced this way is considered part of this prospectus supplement, and any information filed with the SEC subsequent to the date of this prospectus supplement will automatically be deemed to update and supersede this information. We incorporate by reference the following documents (except for "furnished" information described below) which have been filed with the SEC:

        We also incorporate by reference all documents we may subsequently file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 after the date of this prospectus supplement until the termination of the offering.

        Information furnished under Items 2.02 or 7.01 (or corresponding information furnished under Item 9.01 or included as an exhibit) in any past or future Current Report on Form 8-K (including the Current Reports on Form 8-K listed above) that we file with the SEC, unless otherwise expressly specified in such report, is not incorporated by reference in this prospectus supplement.

        We will provide without charge upon written or oral request, a copy of any or all of the documents which are incorporated by reference into this prospectus supplement. Requests should be directed to:

Occidental Petroleum Corporation
10889 Wilshire Boulevard
Los Angeles, California 90024
Attn: Robert J. Williams
Telephone: (310) 208-8800

        You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus and any applicable free writing prospectuses. We have not authorized any person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not making an offer to sell

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these securities in any jurisdiction where the offer or sale is not permitted. The information contained in this prospectus supplement and the accompanying prospectus is accurate only as of the respective dates on the front covers of this prospectus supplement and the accompanying prospectus, the information contained in any related free writing prospectus will be accurate only as of the date of that document, and the information contained in any document incorporated by reference in this prospectus supplement is accurate only as the date of such document. Our business, financial condition, results of operations and prospects may have changed since those respective dates.

        Except as provided above, no other information, including information on our internet site, is incorporated by reference in this prospectus supplement, the accompanying prospectus or any free writing prospectus.

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Prospectus

OCCIDENTAL PETROLEUM CORPORATION

LOGO

Senior Debt Securities



        We may offer, issue and sell senior debt securities from time to time.

        We may offer and sell these senior debt securities to or through one or more underwriters, dealers and agents, or directly to purchasers, on a continuous or delayed basis.

        This prospectus describes some of the general terms that may apply to these senior debt securities. The specific terms of any senior debt securities to be offered will be described in a supplement to this prospectus. The prospectus supplement may also add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement carefully before you make your investment decision.

        Investing in our senior debt securities involves risks. See "Risk Factors" in our most recent annual report on Form 10-K, which is incorporated herein by reference, in any of our subsequently filed quarterly and current reports that are incorporated herein by reference and in any applicable prospectus supplement.



        This prospectus may not be used to sell senior debt securities unless accompanied by a prospectus supplement.



        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus or the accompanying prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.



        The date of this prospectus is August 15, 2011.


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TABLE OF CONTENTS

 
  Page  

About This Prospectus

    i  

Risk Factors

   
1
 

Forward-Looking Statements

   
1
 

Where You Can Find More Information

   
2
 

Occidental

   
3
 

Use of Proceeds

   
4
 

Description of Senior Debt Securities

   
4
 

Plan of Distribution

   
17
 

Legal Matters

   
18
 

Experts

   
18
 


ABOUT THIS PROSPECTUS

        Unless otherwise stated or the context otherwise requires, the terms "Occidental," "we," "us" and "our" refer to Occidental Petroleum Corporation and not any of its subsidiaries.

        This prospectus is part of a registration statement we filed with the Securities and Exchange Commission (the "SEC") using a "shelf" registration process. Under this shelf registration process, we may from time to time sell the senior debt securities described in this prospectus in one or more offerings.

        This prospectus describes some of the general terms that may apply to these senior debt securities. The specific terms of any senior debt securities to be offered will be described in a supplement to this prospectus. The prospectus supplement may also add, update or change information contained in this prospectus. You should read carefully this prospectus and the applicable prospectus supplement together with any additional information described under the heading "Where You Can Find More Information" before you make your investment decision.


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RISK FACTORS

        Investing in our senior debt securities involves risks. You should carefully consider the risk factors incorporated by reference in this prospectus and included in any accompanying prospectus supplement. Specifically, please see "Risk Factors" included in our Annual Report on Form 10-K for the year ended December 31, 2010 and the other information in that and the other reports that we file with the SEC that are incorporated by reference in this prospectus for a discussion of risk factors that may affect our business. Realization of any of those risks or the risks disclosed in any accompanying prospectus supplement or adverse results from any matter listed under the heading "Forward-Looking Statements" in this prospectus, in any accompanying prospectus supplement or in any such reports could have a material adverse effect on our business, financial condition, cash flows and results of operations, and you might lose all or part of your investment.


FORWARD-LOOKING STATEMENTS

        This prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein contain forward-looking statements and involve risks and uncertainties that could materially affect expected results of operations, liquidity, cash flows and business prospects. Factors that could cause results to differ materially include, but are not limited to:

        Words such as "estimate," "project," "predict," "will," "would," "should," "could," "may," "might," "anticipate," "aim," "goal," "target," "objective," "plan," "intend," "believe," "expect" or similar expressions that convey the uncertainty of future events or outcomes generally indicate forward-looking statements. You should not place undue reliance on these forward-looking statements, which speak only as of the date of this prospectus or, in the case of documents incorporated by reference, as of the date of those documents. Unless legally required, we do not undertake any obligation to update any forward-looking statements, as a result of new information, future events or otherwise. Certain risks

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that may affect our results of operations and financial position appear under the heading "Risk Factors" and elsewhere in our most recent annual report on Form 10-K, which is incorporated herein by reference, as well as in any of our subsequently filed quarterly or current reports that are incorporated herein by reference and any applicable prospectus supplement.


WHERE YOU CAN FIND MORE INFORMATION

        We file annual, quarterly and current reports, proxy statements and other information with the SEC. You may read and copy any document we file at the SEC's Public Reference Room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the Public Reference Room. The SEC also maintains a website at www.sec.gov that contains reports, proxy statements and other information regarding issuers that file electronically with the SEC, including us. These reports, proxy statements and other information can also be read through the Investor Relations section of our website at www.oxy.com. Information on our website does not constitute part of, and is not incorporated by reference in, this prospectus and should not be relied upon in connection with making any investment decision with respect to our securities.

        The SEC allows us to "incorporate by reference" the information that we file with the SEC. This permits us to disclose important information to you by referencing these filed documents. Any information referenced this way is considered part of this prospectus, and any information filed with the SEC subsequent to the date of this prospectus, or contained in any accompanying prospectus supplement or related free-writing prospectus, will automatically be deemed to update and supersede this information. We incorporate by reference the following documents (except for "furnished" information described below) which have been filed with the SEC:

        We also incorporate by reference all documents we may subsequently file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 after the initial filing date of the registration statement of which this prospectus is a part and prior to the termination of the offering.

        Information furnished under Items 2.02 or 7.01 (or corresponding information furnished under Item 9.01 or included as an exhibit) in any past or future Current Report on Form 8-K (including the Current Reports on Form 8-K listed above) that we file with the SEC, unless otherwise expressly specified in such report, is not incorporated by reference in this prospectus.

        We will provide without charge upon written or oral request, a copy of any or all of the documents which are incorporated by reference into this prospectus. Requests should be directed to:

Occidental Petroleum Corporation
10889 Wilshire Boulevard
Los Angeles, California 90024
Attn: Robert J. Williams
Telephone: (310) 208-8800

        You should rely only on the information contained or incorporated by reference in this prospectus and any accompanying prospectus supplements and any applicable free writing prospectuses. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We are not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. The information contained

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in this prospectus is accurate only as of the date on the front cover of this prospectus, the information contained in any accompanying prospectus supplement or related free writing prospectus will be accurate only as of the date of that document, and the information contained in any document incorporated by reference in this prospectus is accurate only as the date of such document. Our business, financial condition, results of operations and prospects may have changed since that date.

        Except as provided above, no other information, including information on our internet site, is incorporated by reference in this prospectus.


OCCIDENTAL

        Our principal businesses consist of three segments operated by our subsidiaries and affiliates. The oil and gas segment explores for, develops, produces and markets crude oil, including natural gas liquids (NGLs) and condensate (together with NGLs, "liquids"), as well as natural gas. The chemical segment manufactures and markets basic chemicals, vinyls and other chemicals. The midstream, marketing and other segment gathers, treats, processes, transports, stores, purchases and markets crude oil, liquids, natural gas, carbon dioxide and power. It also trades around its assets, including pipelines and storage capacity, and trades oil and gas, other commodities and commodity-related securities. Our principal executive offices are located at 10889 Wilshire Boulevard, Los Angeles, California 90024; telephone (310) 208-8800.

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USE OF PROCEEDS

        Unless we inform you otherwise in a prospectus supplement, the net proceeds we receive from the sale of senior debt securities, if any, offered under this prospectus may be used for general corporate purposes, including working capital, acquisitions, retirement of debt, stock repurchases and other business opportunities.


DESCRIPTION OF SENIOR DEBT SECURITIES

General

        We may issue one or more series of senior debt securities pursuant to this prospectus. We may issue the senior debt securities under an indenture (the "Senior Indenture") to be entered into between us and The Bank of New York Mellon Trust Company, N.A., as trustee ("Senior Indenture Trustee"). The form of Senior Indenture is included as an exhibit to the registration statement of which this prospectus is a part.

        Below is a description of certain general terms of the senior debt securities. The description is not complete and is subject to and qualified in its entirety by reference to the Senior Indenture. The particular terms of a series of senior debt securities will be described in a prospectus supplement and, if applicable, a pricing supplement. Capitalized terms used but not defined in this summary have the meanings specified in the Senior Indenture.

        The senior debt securities will rank equally with all of our unsecured and unsubordinated debt. The Senior Indenture is subject to the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act"). The Senior Indenture does not limit the amount of senior debt securities which we may issue, nor does it limit us or our subsidiaries from issuing any other unsecured debt. Such other unsecured debt may have different terms than the senior debt securities. Our previously issued and outstanding senior debt does have different terms than the senior debt securities (including different restrictive covenants and event of default provisions). The terms of the senior debt securities issued under this prospectus will only be as described in the Senior Indenture, this prospectus and any prospectus supplement.

        Each prospectus supplement, together with a pricing supplement, if applicable, will describe the terms relating to a series of senior debt securities, which may include:

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        Each prospectus supplement or pricing supplement, as applicable, may describe certain United States federal income tax considerations applicable to the purchase, holding and disposition of the senior debt securities that the prospectus supplement or pricing supplement covers, as applicable.

Limitation on Liens

        We will not, nor will we permit any Consolidated Subsidiary (as defined below) to, incur, create, assume, guarantee or otherwise become liable with respect to any Secured Debt (as defined below), unless the senior debt securities are secured equally and ratably with (or prior to) such Secured Debt. This covenant will not apply to:

        Notwithstanding the foregoing, we and one or more Consolidated Subsidiaries may incur, create, assume, guarantee or otherwise become liable with respect to any Secured Debt that would otherwise be subject to the foregoing restrictions if, after giving effect thereto, the aggregate amount of all Secured Debt, together with the Discounted Rental Value (as defined below) in respect of sale and leaseback transactions involving Principal Domestic Properties (excluding sale and leaseback transactions exempted from the restrictions discussed below under the caption "—Limitations on Sale

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and Leaseback Transactions" pursuant to clause (1) or (2) of the second paragraph under such caption), would not exceed 15% of Consolidated Net Tangible Assets (as defined below).

Limitations on Sale and Leaseback Transactions

        We will not, nor will we permit any Consolidated Subsidiary to, sell or transfer any Principal Domestic Property (as defined below), with us or any Consolidated Subsidiary taking back a lease of such Principal Domestic Property, unless:

This restriction will not apply to any sale and leaseback transaction (1) between us and a Consolidated Subsidiary or between Consolidated Subsidiaries or (2) involving the sale or transfer of any Principal Domestic Property with a lease for a period, including renewals, of not more than 36 months.

Certain Definitions

        "Business Entity" means a corporation, association, business trust, partnership, limited liability company or other business entity.

        "Capital Stock" means (a) in the case of a corporation, common stock, preferred stock and any other capital stock, (b) in the case of a partnership, partnership interests (whether general or limited), (c) in the case of a limited liability company, limited liability company interests, and (d) in the case of any other Business Entity, any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distribution of assets of, such Business Entity, but excluding from all of the foregoing any debt securities convertible into Capital Stock, whether or not such debt securities include any right of participation with Capital Stock.

        "Consolidated Net Tangible Assets" means the total of the Net Tangible Assets of us and our Consolidated Subsidiaries, included in our and our Consolidated Subsidiaries' financial statements prepared on a consolidated basis in accordance with United States generally accepted accounting principles, after eliminating all intercompany items.

        "Consolidated Subsidiary" means any Subsidiary included in our and our Subsidiaries' financial statements prepared on a consolidated basis in accordance with United States generally accepted accounting principles.

        "Current Liabilities" means all Indebtedness that may properly be classified as current liabilities in accordance with United States generally accepted accounting principles.

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        "Discounted Rental Value" means, as to any particular lease under which any Person is at the time liable and at any date as of which the amount thereof is to be determined, the total net amount of rent (after deducting the amount of rent to be received by such Person under noncancelable subleases) required to be paid by such Person under such lease during the remaining noncancelable term thereof (including any such period for which such lease has been extended or may, at the option of the lessor, be extended), discounted from the respective due dates thereof to such date at a rate per annum of 113/4%. The net amount of rent required to be paid under any such lease for any such period shall be the aggregate amount of the rent payable by the lessee with respect to such period, after excluding amounts required to be paid on account of maintenance and repairs, insurance, taxes, water rates and similar charges. In the case of any lease which is terminable by the lessee upon the payment of a penalty, such net amount shall also include the amount of such penalty, but no rent shall be considered as required to be paid under such lease subsequent to the first date upon which it may be so terminated. If and to the extent the amount of any rent during any future period is not definitely determinable under the lease in question, the amount of such rent shall be estimated in such reasonable manner as our Board of Directors may in good faith determine.

        "Funded Debt" means all Indebtedness maturing one year or more from the date of the creation thereof, all Indebtedness directly or indirectly renewable or extendible, at the option of the debtor, by its terms or by the terms of any instrument or agreement relating thereto, to a date one year or more from the date of the creation thereof, and all Indebtedness under a revolving credit or similar agreement obligating the lender or lenders to extend credit over a period of one year or more, even though such Indebtedness may also conform to the definition of Short-Term Borrowing.

        "Indebtedness," as applied to a Person, means, as of the date on which Indebtedness is to be determined (a) all items (except items of Capital Stock or of surplus or of deferred credits or noncontrolling interest in Subsidiaries) which, in accordance with United States generally accepted accounting principles in effect from time to time, would be included in determining total liabilities, as shown on the liability side of a balance sheet of such Person; (b) all indebtedness secured by any mortgage on any property or asset owned or held by such Person subject thereto, whether or not the indebtedness secured thereby has been assumed; and (c) all indebtedness of others which such Person has directly or indirectly guaranteed, endorsed (otherwise than for collection or deposit in the ordinary course of business), discounted with recourse, agreed (contingently or otherwise) to purchase or repurchase or otherwise acquire, or in respect of which such Person has otherwise become directly or indirectly liable. For the purpose of computing Indebtedness of any Person, there shall be excluded any particular Indebtedness which meets one or more of the following categories:

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        "Lien" means and includes any mortgage, pledge, lien, security interest, conditional sale or other title retention agreement or other similar encumbrance to secure Indebtedness for borrowed money, but excluding (i) any security interest which a lessor may be deemed to have under a lease and (ii) any lien which may be deemed to exist under a Production Payment or under any subordination arrangement.

        "Net Tangible Assets" of any specified Person means the total of all assets properly appearing on a balance sheet of such Person prepared in accordance with United States generally accepted accounting principles, after deducting from such total, without duplication of deductions, (a) all Current Liabilities of such Person; (b) that portion of the book amount of all such assets which would be treated as intangibles under United States generally accepted accounting principles, including, without limitation, all such items as goodwill, trademarks, trade names, brands, copyrights, patents, licenses and rights with respect to the foregoing and unamortized debt discount and expense; and (c) the amount, if any, at which any Capital Stock of such Person appears on the asset side of such balance sheet.

        "Original Issue Discount Security" means any senior debt security which provides for an amount less than the principal amount thereof to be due and payable upon a declaration of acceleration of the Maturity thereof pursuant to the Senior Indenture.

        "Person" means any individual, corporation, partnership, limited liability company, joint venture, association, joint-stock company, trust, unincorporated organization or government or any agency or political subdivision thereof.

        "Principal Domestic Property" means any (1) developed oil or gas producing property or (2) processing or manufacturing plant, in each case which we or any Consolidated Subsidiary own or lease as of the date of the Senior Indenture or thereafter and which is located in the continental United States (provided, however, that any such property or plant declared by our Board of Directors by Board Resolution not to be of material importance to our and our Consolidated Subsidiaries' business, taken as a whole, will be excluded from the foregoing definition).

        "Production Payment" means any economic interest in oil, gas or mineral reserves which (1) entitles the holder thereof to a specified share of future production from such reserves, free of the costs and expenses of such production, and (2) terminates when a specified quantity of such share of future production from such reserves has been delivered or a specified sum has been realized from the sale of such share of future production from such reserves.

        "Redemption Date" when used with respect to any senior debt security to be redeemed, means the date fixed for such redemption by or pursuant to the Senior Indenture.

        "Secured Debt" means any Indebtedness of us or any Consolidated Subsidiary for borrowed money, secured by a Lien on any Principal Domestic Property or on any shares of Capital Stock or on any Indebtedness of any Consolidated Subsidiary which owns any Principal Domestic Property.

        "Short-Term Borrowing" means all Indebtedness in respect of borrowed money maturing on demand or within one year from the date of the creation thereof and not directly or indirectly renewable or extendible, at the option of the debtor, by its terms or by the terms of any instrument or

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agreement relating thereto, to a date one year or more from the date of the creation thereof; provided that Indebtedness in respect of borrowed money arising under a revolving credit or similar agreement which obligates the lender or lenders to extend credit over a period of one year or more will constitute Funded Debt and not Short-Term Borrowing, even though it matures on demand or within one year from the date as of which such Short-Term Borrowing is to be determined.

        "Subsidiary" means a Business Entity more than 50% of the outstanding Voting Stock of which is owned, directly or indirectly, by us or by one or more of our other Subsidiaries, or by us and one or more of our other Subsidiaries.

        "Voting Stock" means, with respect to any Business Entity, any class or series of Capital Stock of such Business Entity the holders of which are ordinarily, in the absence of contingencies, entitled to vote for the election of, or to appoint or to approve the appointment of, the directors, trustees or managing members of, or other persons holding similar positions with, such Business Entity.

Consolidation, Merger or Sale

        The Senior Indenture generally permits us to consolidate with, merge into or convey, transfer or lease our properties and assets substantially as an entirety, to any Business Entity, so long as, immediately after giving effect to such transaction, no event of default under the Senior Indenture or event which, after notice or lapse of time or both, would become an event of default shall have occurred and be continuing. However, any successor or acquiror of such assets must assume all of our obligations under the Senior Indenture and the senior debt securities and be organized and existing under the laws of the United States of America, any state thereof or the District of Columbia.

Events of Default Under the Senior Indenture

        The following are events of default under the Senior Indenture with respect to each series of senior debt securities:

        If an event of default with respect to senior debt securities of any series occurs and is continuing, the Senior Indenture Trustee or the holders of at least 25% in principal amount of the outstanding senior debt securities of that series, by notice in writing to us (and to the Senior Indenture Trustee if notice is given by such holders), may declare the principal of (or if such senior debt securities are Original Issue Discount Securities, the portion of the principal amount specified in the applicable prospectus supplement or pricing supplement, if any), and accrued interest, if any, on the senior debt securities of such series to be due and payable immediately. At any time after such a declaration of acceleration has been made and before a judgment or decree for payment of the money due has been obtained holders of a majority in principal amount of the outstanding senior debt securities of that

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series, by written notice to us and the Senior Indenture Trustee, may rescind and annul such declaration and its consequences if:

        The holders of a majority in principal amount of the outstanding senior debt securities of any series may waive any past default with respect to that series and its consequences, except defaults regarding:

        Any waiver shall cure such default and the corresponding event of default.

        Subject to the terms of the Senior Indenture, the Senior Indenture Trustee will be under no obligation to exercise any of its rights or powers under the Senior Indenture at the request or direction of any of the holders of the applicable series of senior debt securities, unless the holders have offered the Senior Indenture Trustee reasonable security or indemnity against costs, expenses and liabilities to be incurred in compliance with such request. The holders of a majority in principal amount of the outstanding senior debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the Senior Indenture Trustee, or exercising any trust or power conferred on the Senior Indenture Trustee, with respect to the senior debt securities of that series, provided that:

        A holder of the senior debt securities of any series will have the right to institute a proceeding under the Senior Indenture or to appoint a receiver or trustee, or to seek other remedies only if:

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        The Senior Indenture provides that no holder or group of holders of senior debt securities will have any right to affect, disturb or prejudice the rights of other holders, obtain or seek priority or preference over another holder or enforce its rights under the Senior Indenture except as provided in the Senior Indenture for the equal and ratable benefit of all holders.

        These limitations on instituting proceedings do not apply to a suit instituted by a holder of senior debt securities to enforce the payment of the principal of or interest on the senior debt securities.

        We will periodically file statements with the Senior Indenture Trustee regarding our compliance with the conditions and covenants in the Senior Indenture.

Modification of Senior Indenture; Waiver

        We and the Senior Indenture Trustee may amend or supplement the Senior Indenture without the consent of any holders to, among other things:

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        In addition, under the Senior Indenture, the rights of holders of a series of senior debt securities may be changed by us and the Senior Indenture Trustee with the written consent of the holders of at least a majority in principal amount of the outstanding senior debt securities of each series that is affected. However, no change may be made without the consent of the holder of each outstanding senior debt security affected if such change would, among other things:

Form, Exchange and Transfer

        The senior debt securities of each series may be issued as registered securities, as bearer securities (with or without coupons) or both. Unless otherwise specified in the applicable prospectus supplement or the pricing supplement, if any, registered securities will be issued in denominations of $1,000 and any integral multiple thereof and bearer securities will be issued in denominations of $5,000 and $100,000. Subject to the terms of the Senior Indenture and the limitations applicable to global securities described in the applicable prospectus supplement or the pricing supplement, if any, registered securities will be exchangeable for other registered securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

        Subject to the terms of the Senior Indenture and the limitations applicable to global senior debt securities set forth in the applicable prospectus supplement or pricing supplement, if any, senior debt securities issued as registered securities may be presented for exchange or for registration of transfer (duly endorsed or with the form of transfer duly executed) at the office of the registrar or at the office

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of any transfer agent we designate for that purpose. Unless otherwise provided in the senior debt securities to be transferred or exchanged, no service charge will be made for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges. We have appointed the Senior Indenture Trustee as registrar. Any transfer agent (in addition to the registrar) initially designated by us for any senior debt securities will be named in the applicable prospectus supplement or pricing supplement. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the senior debt securities of each series.

        If the senior debt securities of any series are to be redeemed, we will not be required to:

Global Senior Debt Securities

        The senior debt securities of each series may be issued in whole or in part in global form. A senior debt security in global form will be deposited with, or on behalf of, a depositary, which will be named in an applicable prospectus supplement or pricing supplement, if any. A global senior debt security may be issued in either registered or bearer form and in either temporary or definitive form. A global senior debt security may not be transferred, except as a whole, among the depositary for that senior debt security and its nominees and their respective successors. If any senior debt securities of a series are issuable as global senior debt securities, the applicable prospectus supplement or pricing supplement, if any, will describe any circumstances when beneficial owners of interests in that global senior debt security may exchange their interests for definitive senior debt securities of like series and tenor and principal amount in any authorized form and denomination.

Discharge

        Unless otherwise indicated in an applicable prospectus supplement or pricing supplement, if any, we may terminate at any time our obligations under the Senior Indenture with respect to any series of senior debt securities (other than certain limited obligations, such as the obligation to transfer and exchange senior debt securities of that series) by (1)(a) delivering all of the outstanding senior debt securities of that series to the Senior Indenture Trustee to be cancelled or (b) depositing with the Senior Indenture Trustee in trust funds or non-callable United States government or government-guaranteed obligations sufficient without reinvestment to pay all remaining principal and interest on the series of senior debt securities and (2) complying with certain other provisions of the Senior Indenture.

        If we elect to discharge our obligations by depositing cash or United States government or government guaranteed obligations as described above, under present law such discharge is likely to be treated for United States federal income tax purposes as a redemption of the senior debt securities of

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that series prior to maturity in exchange for the property deposited in trust. In that event, each holder would generally recognize, at the time of discharge, gain or loss for United States federal income tax purposes measured by the difference between (1) the sum of (a) the amount of any cash and (b) the fair market value of any property deposited in trust deemed received by such holder (unless attributable to accrued interest) and (2) such holder's tax basis in the senior debt securities deemed surrendered. After the discharge, each such holder would likely be treated as if it held an undivided interest in the cash (or investments made therewith) and the property held in trust (or investments made with interest received therefrom). Each such holder would generally be subject to tax liability in respect of interest income and original issue discount, if applicable, thereon and would recognize any gain or loss upon any disposition, including redemption, of the assets held in trust. Although tax might be owed, the holder of a discharged senior debt security would not receive cash (except for current payments of interest on that senior debt security) until the maturity or earlier redemption (or, if applicable, repurchase by us at the option of the holder) of that senior debt security. United States federal income tax treatment of this nature could affect the purchase price that a holder would receive upon the sale of the senior debt securities. You are urged to consult with your tax advisor regarding the tax consequences of the discharge of our obligations.

Information Concerning the Senior Indenture Trustee

        The Senior Indenture Trustee, other than during the occurrence and continuance of an event of default under the Senior Indenture, undertakes to perform only those duties as are specifically set forth in the Senior Indenture and, upon an event of default under the Senior Indenture, must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the Senior Indenture Trustee is under no obligation to exercise any of the rights or powers given it by the Senior Indenture at the request or direction of any holder of senior debt securities unless the Senior Indenture Trustee is offered reasonable security or indemnity by that holder against the costs, expenses and liabilities that it might incur. The Senior Indenture Trustee is not required to spend or risk its own money or otherwise become financially liable while performing its duties unless it reasonably believes that it will be repaid or receive adequate indemnity.

        The Bank of New York Mellon is a participating lender under our revolving credit agreement and provides commercial banking services to us and our affiliates. The Bank of New York Mellon Trust Company, N.A. is the Senior Indenture Trustee. However, if The Bank of New York Mellon Trust Company, N.A. acquires any conflicting interest when an event of default is pending, it must (with certain exceptions) eliminate the conflict or resign.

Payment and Payment Agents

        The person in whose name a senior debt security is registered will be treated as the owner of such security for the purpose of receiving payment of principal and, unless otherwise indicated in an applicable prospectus supplement or pricing supplement, if any, interest on such senior debt security and for all other purposes.

        Unless otherwise indicated in the applicable prospectus supplement or pricing supplement, if any, payment of interest on any senior debt securities (other than bearer securities) on any interest payment date will be made to the person in whose name those senior debt securities (or one or more predecessor securities) are registered at the close of business on the regular record date for the interest. Unless otherwise indicated in the applicable prospectus supplement or pricing supplement, if any, principal and interest on the senior debt securities of a particular series will be payable at the office of the paying agents that we designate, except that payments of interest (other than interest on bearer securities) may, at our option, be made by wire transfer or check mailed to the address of the person entitled thereto. Unless otherwise indicated in an applicable prospectus supplement or pricing

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supplement, if any, any payment of an installment of interest on any bearer security will be made only if the coupon relating to the interest installment is surrendered.

        We will be required to maintain a paying agent in each place of payment for the senior debt securities of a particular series. Unless otherwise indicated in the applicable prospectus supplement or pricing supplement, if any, the corporate trust office of the Senior Indenture Trustee in The City of New York will be designated as the paying agent for payments with respect to senior debt securities (other than bearer securities).

        All moneys that we pay to a paying agent or the Senior Indenture Trustee for the payment of the principal or interest, if any, on any senior debt securities which remain unclaimed at the end of two years after that principal or interest has become due and payable will be repaid to us, and the holder of the security thereafter may look only to us for payment thereof.

        Unless otherwise indicated in an applicable prospectus supplement or pricing supplement, if any, interest shall be computed, for fixed rate securities, on the basis of a 360-day year comprised of twelve 30-day months, and, for variable rate securities, on the basis of the actual number of days in the interest period divided by 360.

Governing Law

        The Senior Indenture and senior debt securities will be governed by and construed in accordance with the law of the State of New York (without regard to conflicts of laws principles thereof).

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PLAN OF DISTRIBUTION

        We may sell the senior debt securities being offered hereby in one or more of the following ways from time to time:

        The prospectus supplements and pricing supplements, if any, will set forth the terms of the offering of each series of senior debt securities, including the name or names of any underwriter, dealers or agents, the purchase price of the senior debt securities and the proceeds to us from such sale, any underwriting discounts or agency fees and other items constituting underwriters' or agents' compensation, any initial public offering price, any discounts or concessions allowed or reallowed or paid to dealers and any securities exchanges on which the senior debt securities may be listed.

        If underwriters or dealers are used in the sale, the senior debt securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions, including privately negotiated transactions, at a fixed public offering price or prices, which may be changed, in "at the market offerings," at prices related to prevailing market prices or at negotiated prices or varying prices determined at the time of sale.

        Unless otherwise set forth in a prospectus supplement or a pricing supplement, if any, the obligations of the underwriters to purchase any series of senior debt securities will be subject to certain conditions precedent and the underwriters will be obligated to purchase all of the series of senior debt securities, if any are purchased.

        If a dealer is utilized in the sale of senior debt securities, we will sell the senior debt securities to the dealer, as principal. The dealer may then resell the senior debt securities to the public at varying prices to be determined by the dealer at the time of resale. The names of the dealers and the terms of the transaction will be set forth in the prospectus supplement relating to that transaction.

        Senior debt securities may also be offered and sold, if so indicated in the prospectus supplement or a pricing supplement, if any, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms ("remarketing firms") acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the prospectus supplement or a pricing supplement, if any.

        Underwriters, agents, dealers and remarketing firms may be entitled under agreements entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments which the underwriters or agents may be required to make in respect thereof, and to reimbursement by us for certain expenses. Underwriters, agents, dealers and remarketing firms may be customers of, engage in transactions with, or perform services for us and our affiliates in the ordinary course of business.

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        Each series of senior debt securities will be a new issue of senior debt securities and will have no established trading market. Unless otherwise specified in the applicable prospectus supplement or pricing supplement, the senior debt securities will not be listed on a national securities exchange. Any underwriters to whom we sell senior debt securities for public offering and sale may make a market in those senior debt securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice.


LEGAL MATTERS

        Unless otherwise specified in a prospectus supplement accompanying this prospectus a senior attorney in our legal department will provide opinions regarding the authorization and validity of the senior debt securities. Any underwriters will be advised about legal matters by their own counsel, which will be named in the prospectus supplement.


EXPERTS

        The consolidated financial statements and financial statement schedule of Occidental Petroleum Corporation and its subsidiaries as of December 31, 2010 and 2009, and for each of the years in the three-year period ended December 31, 2010, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2010 have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

        Ryder Scott Company, L.P., independent petroleum engineering consultants, reviewed Occidental's oil and gas estimation process, which review information is included in Occidental's Annual Report on Form 10-K for the year ended December 31, 2010, which is incorporated by reference in this prospectus. Ryder Scott's review information is incorporated by reference herein in reliance upon the authority of said firm in such matters.

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Occidental Petroleum Corporation

$1,250,000,000 1.750% Senior Notes due 2017

$900,000,000 3.125% Senior Notes due 2022

LOGO



PROSPECTUS SUPPLEMENT



Joint Book-Running Managers

Barclays Capital   Citigroup   J.P. Morgan

BofA Merrill Lynch   Wells Fargo Securities



Mitsubishi UFJ Securities   RBS   SOCIETE GENERALE   BNP PARIBAS
BNY Mellon Capital Markets, LLC   Credit Suisse   Scotia Capital   UBS Investment Bank
BBVA   Mizuho Securities   Banca IMI   Standard Chartered Bank



August 15, 2011