LYB LyondellBasell Industries NV

DESCRIPTION OF THE NOTES

        The notes will be issued under and pursuant to an indenture dated as of March 2, 2016 (the "base indenture") among LYB International Finance II, as issuer, LyondellBasell, as guarantor, and Deutsche Bank Trust Company Americas, as trustee, as amended and supplemented by a supplemental indenture to be dated as of September 17, 2019 between LYB International Finance II, as issuer, LyondellBasell, as guarantor, and Deutsche Bank Trust Company Americas, as trustee (the "supplemental indenture" and together with the base indenture, the "indenture"). The notes will be issued pursuant to the supplemental indenture, or a resolution of LYB International Finance II's managing board, and an accompanying officer's certificate, in either case, setting forth the specific terms applicable to each series of notes.

        This description of the notes is intended to be an overview of the material provisions of the notes and is intended to supplement, and to the extent of any inconsistency replace, the description of the general terms and provisions of the debt securities set forth in the accompanying prospectus, to which we refer you. Since this description of the notes is only a summary, you should refer to the indenture and the notes, forms of which have been filed as an exhibit to the registration statement of which this prospectus supplement forms a part, for a complete description of the obligations of the issuer and the guarantor under the notes, the guarantees and the indenture and your rights as a holder of the notes.

        The 2026 Notes.    The 2026 notes will:

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constitute a new series of debt securities issued under the indenture and will be initially limited to an aggregate principal amount of €500,000,000; and



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mature on September 17, 2026.

        The 2031 Notes.    The 2031 notes will:

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constitute a new series of debt securities issued under the indenture and will be initially limited to an aggregate principal amount of €500,000,000; and



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mature on September 17, 2031.

        The 2026 notes and the 2031 notes each constitute a separate series of debt securities under the indenture.

        The Notes.    Each series of notes will:

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be the general unsecured, senior obligations of LYB International Finance II;



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be fully and unconditionally guaranteed by LyondellBasell;



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not be entitled to the benefit of any sinking fund;



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be initially issued in minimum denominations of €100,000 and integral multiples of €1,000 in excess thereof; and



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be issued in book-entry form, the Global Notes deposited with the Common Safekeeper for the accounts of Clearstream and Euroclear (each as defined below) and issued to and registered in the name of the nominee of the Common Safekeeper. See "—Book-Entry; Delivery and Form; Global Notes."

        Interest on the notes.    Interest on the notes will:

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accrue at the rate of 0.875% per annum in the case of the 2026 notes and 1.625% per annum in the case of the 2031 notes;



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accrue from September 17, 2019 or the most recent interest payment date;

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be payable in cash annually in arrears on September 17 of each year, beginning on September 17, 2020;



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be payable to holders of record on the Clearing System Business Day immediately preceding the related interest payment date; and



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be computed on the basis of the actual number of days in the period for which interest is being calculated and the actual number of days from and including the date from which interest begins to accrue for the period (or from the issue date of the notes if no interest has been paid on the notes) to, but excluding the next scheduled interest payment date. This payment convention is referred to as Actual/Actual (ICMA) as defined in the rulebook of the International Capital Markets Association.

        "Clearing System Business Day" means Monday to Friday, except December 25 and January 1.

Issuance in Euro

        Initial holders will be required to pay for the notes in euro, and all payments of interest and principal, including payments made upon any redemption of the notes, will be payable in euro. If, on or after the date of this prospectus supplement, the euro is unavailable to us due to the imposition of exchange controls or other circumstances beyond our control or if the euro is no longer being used by the then member states of the European Economic and Monetary Union that have adopted the euro as their currency or for the settlement of transactions by public institutions of or within the international banking community, then all payments in respect of the notes will be made in dollars until the euro is again available to us or so used. The amount payable on any date in euro will be converted into dollars on the basis of the most recently available market exchange rate for euro. Any payment in respect of the notes so made in dollars will not constitute an event of default under the notes or the indenture governing the notes. Neither the trustee nor the paying agent shall have any responsibility for any calculation or conversion in connection with the foregoing.

        Investors will be subject to foreign exchange risks as to payments of principal and interest that may have important economic and tax consequences to them. See "Risk Factors."

        As of September 10, 2019, the euro/U.S. dollar exchange rate was €1.00 = U.S.$1.10385, as published by Bloomberg L.P.

        The notes and the securities of any other series under the indenture will vote together as a single class in many circumstances. To the extent that any other securities are issued under the indenture and denominated in a currency other than euro, the principal amount of the notes and such other securities for purposes of any act, consent or waiver under the indenture shall be determined as the dollar equivalent thereof, converted based on the spot rate (as determined by LYB International Finance II in its discretion) at 11:00 a.m. New York City time on the Business Day (as defined under "—Optional Redemption") before the record date for such act, waiver or consent (or, if there is no such record date, the date when such act, consent or waiver is taken).

Ranking

        The notes and the guarantees will constitute senior unsecured obligations of LYB International Finance II and LyondellBasell, respectively, and will rank equally in right of payment with all other existing and future senior unsecured indebtedness of LYB International Finance II and LyondellBasell, respectively, and will rank senior in right of payment to any future subordinated indebtedness that LYB international Finance II or LyondellBasell incurs, respectively. The notes and the guarantees will be effectively subordinated to any future secured indebtedness of LYB International Finance II and LyondellBasell, respectively, to the extent of the value of the collateral securing such obligation. In addition, the notes will be structurally subordinated to all existing and future liabilities of the

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subsidiaries of LYB International Finance II and LyondellBasell (other than LYB International Finance II).

        At June 30, 2019, LyondellBasell had approximately $10,402 million of indebtedness outstanding, including approximately $7,439 million of indebtedness outstanding of its subsidiaries (including approximately $2,446 million of unsecured indebtedness of LYB International Finance, approximately $1,873 million of unsecured indebtedness of LYB International Finance II and approximately $2,000 million of unsecured indebtedness of LYB Americas Finance) and on a pro forma basis after giving effect to the offering of the notes (and the use of proceeds therefrom), would have had approximately $12,501 million of indebtedness outstanding (in each case, excluding intercompany indebtedness and guarantees of indebtedness of joint ventures). LYB International Finance and LYB International Finance II are finance subsidiaries of LyondellBasell with no significant assets of their own other than their intercompany loans advancing the proceeds of the existing guaranteed notes issued by LYB International Finance and LYB International Finance II, respectively. The existing series of notes of LYB International Finance and LYB International Finance II are each guaranteed by LyondellBasell but not by any of LyondellBasell's subsidiaries. At June 30, 2019, LyondellBasell had no secured indebtedness, although subsidiaries of LyondellBasell had approximately $128 million of outstanding secured indebtedness as of such date.

        We will be permitted under the indenture to issue substantial amounts of additional indebtedness in the future.

Optional Redemption

        Prior to the 2026 Par Call Date and the 2031 Par Call Date, the 2026 notes and the 2031 notes, respectively, will be redeemable and repayable, at LYB International Finance II's option, at any time in whole, or from time to time in part, at a price equal to the greater of:

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100% of the principal amount of the notes of such series to be redeemed; and



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with respect to the 2026 notes, the sum of the present values of the remaining scheduled payments of principal and interest (at the rate in effect on the date of calculation of the redemption price) on the notes to be redeemed that would be due if such notes matured on the 2026 Par Call Date (exclusive of interest accrued to the date of redemption) discounted to the date of redemption on an annual basis (Actual/Actual (ICMA)) at the Comparable Government Bond Rate plus 30 basis points, or



•

with respect to the 2031 notes, the sum of the present values of the remaining scheduled payments of principal and interest (at the rate in effect on the date of calculation of the redemption price) on the notes to be redeemed that would be due if such notes matured on the 2031 Par Call Date (exclusive of interest accrued to the date of redemption) discounted to the date of redemption on an annual basis (Actual/Actual (ICMA)) at the Comparable Government Bond Rate plus 35 basis points;

plus, accrued and unpaid interest to, but excluding, the date of redemption.

        On or after the 2026 Par Call Date (with respect to the 2026 notes) and the 2031 Par Call Date (with respect to the 2031 notes), such notes will be redeemable and repayable, at LYB International Finance II's option, at any time in whole, or from time to time in part, at a price equal to 100% of the principal amount of the notes to be redeemed plus accrued and unpaid interest on the notes to be redeemed to, but excluding, the date of redemption.

        Notes called for redemption become due on the date fixed for redemption. Notices of redemption will be mailed at least 30 but not more than 60 days before the redemption date to each holder of record of the notes to be redeemed at its registered address. The notice of redemption for the notes of

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a series will state, among other things, the amount of notes of such series to be redeemed, the redemption date, the redemption price or, if not ascertainable, the manner of determining the redemption price and the place(s) that payment will be made upon presentation and surrender of notes to be redeemed. Unless LYB International Finance II or LyondellBasell defaults in payment of the redemption price, interest will cease to accrue on any notes that have been called for redemption at the redemption date. Notes called for redemption will be redeemed and repaid in principal amounts of €100,000 or any integral multiple of €1,000 in excess thereof. If less than all the notes of a series are redeemed at any time, the trustee will select the notes of such series to be redeemed on a pro rata basis or by any other method the trustee deems fair and appropriate.

        For purposes of determining the optional redemption price, the following definitions are applicable:

        "2026 Par Call Date" means June 17, 2026 (three months prior to the maturity date of the 2026 notes).

        "2031 Par Call Date" means June 17, 2031 (three months prior to the maturity date of the 2031 notes).

        "Business Day" means each day which is not a Legal Holiday (as defined below).

        "Comparable Government Bond Rate" means the yield to maturity, expressed as a percentage (rounded to three decimal places, with 0.0005 being rounded upwards), on the third Business Day prior to the date fixed for redemption, of the Comparable Government Bond (as defined below) on the basis of the middle market price of the Comparable Government Bond prevailing at 11: 00 a.m. (London time) on such Business Day as determined by an independent investment bank selected by LYB International Finance II.

        "Comparable Government Bond" means, in relation to any Comparable Government Bond Rate calculation, at the discretion of an independent investment bank selected by LYB International Finance II, a German government bond whose maturity is closest to the maturity of the notes to be redeemed, calculated as if the maturity date of such notes were the 2026 Par Call Date (with respect to the 2026 notes) or the 2031 Par Call Date (with respect to the 2031 notes), or if such independent investment bank in its discretion determines that such similar bond is not in issue, such other German government bond as such independent investment bank may, with the advice of three brokers of, and/or market makers in, German government bonds selected by LYB International Finance II, determine to be appropriate for determining the Comparable Government Bond Rate.

        "Legal Holiday" means a Saturday, Sunday or other day on which the trustee, registrar and paying agent or banking institutions are not required by law or regulation to be open in the State of New York or London and, for any place of payment outside of New York City or London, in such place of payment, and on which the Trans-European Automated Real-time Gross Settlement Express Transfer system (the TARGET2 system), or any successor thereto, does not operate.

        Except as set forth above and below under "—Redemption for Changes in Taxes," the notes will not be redeemable by LYB International Finance II prior to maturity and will not be entitled to the benefit of any sinking fund.

Defeasance

        The notes will be subject to legal defeasance and to covenant defeasance as provided under "Description of Debt Securities—Defeasance" in the accompanying prospectus.

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Change of Control Offer

        If a change of control triggering event occurs with respect to a series of notes, unless LYB International Finance II has exercised its option to redeem the notes of such series as described above, each holder of outstanding notes of such series will have the right to require LYB International Finance II to make an offer (a "change of control offer") to repurchase all or any portion (equal to €100,000 or an integral multiple of €1,000 in excess thereof) of that holder's notes of such series, on the terms set forth in such notes. In a change of control offer, LYB International Finance II will be required to offer payment in cash equal to 101% of the aggregate principal amount of notes repurchased (a "change of control payment"), plus accrued and unpaid interest, if any, on the notes repurchased to, but excluding, the date of repurchase, subject to the right of holders of record on the applicable record date to receive interest due on the next interest payment date.

        Within 30 days following any change of control triggering event with respect to a series of notes or, at LYB International Finance II's option, prior to any change of control, but after public announcement of the transaction that constitutes or may constitute the change of control, a notice will be mailed to holders of the notes of the applicable series describing the transaction that constitutes or may constitute the change of control triggering event and offering to repurchase such notes on the date specified in the applicable notice, which date will be no earlier than 30 days and no later than 60 days from the date such notice is mailed (a "change of control payment date"). The notice may, if mailed prior to the date of consummation of the change of control, state that the change of control offer is conditioned on the change of control triggering event occurring on or prior to the applicable change of control payment date.

        Upon the change of control payment date, LYB International Finance II will, to the extent lawful:

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accept for payment all notes or portions of notes properly tendered and not withdrawn pursuant to the change of control offer;



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deposit with the paying agent an amount equal to the change of control payment in respect of all notes or portions of notes properly tendered and not withdrawn; and



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deliver or cause to be delivered to the trustee the notes properly accepted together with an officers' certificate stating the aggregate principal amount of notes or portions of notes being repurchased.

        LYB International Finance II will not be required to make a change of control offer with respect to a series of notes upon the occurrence of a change of control triggering event with respect to such series of notes if a third party makes such an offer with respect to such series of notes in the manner, at the times and otherwise in compliance with the requirements for an offer made by LYB International Finance II and the third party repurchases all notes of such series properly tendered and not withdrawn under its offer. In addition, LYB International Finance II will not repurchase any notes of a series if there has occurred and is continuing on the change of control payment date an event of default with respect to such series of notes under the indenture, other than a default in the payment of the change of control payment upon a change of control triggering event with respect to such series of notes.

        LYB International Finance II will comply with the applicable requirements of Rule 14e-1 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of the notes of a series as a result of a change of control triggering event with respect to such series of notes. To the extent that the provisions of any securities laws or regulations conflict with the change of control offer provisions of the notes of a series, LYB International Finance II will comply with those securities laws and regulations and will not be deemed to have breached its obligations under the change of control offer provisions of the notes of such series by virtue of any such conflict.

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        For purposes of the change of control offer provisions of the notes, the following terms will be applicable:

        "change of control" means the occurrence of any of the following: (1) the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or more series of related transactions, of all or substantially all of LyondellBasell's assets and the assets of its subsidiaries, taken as a whole, to any person, other than LyondellBasell or one of its subsidiaries; or (2) LyondellBasell becomes aware of (by way of a report or any other filing pursuant to Section 13(d) of the Exchange Act, proxy, vote, written notice or otherwise) the acquisition by any person or group (within the meaning of Section 13(d)(3) or Section 14(d)(2) of the Exchange Act, or any successor provision), including any group acting for the purpose of acquiring, holding or disposing of securities (within the meaning of Rule 13d-5(b)(1) under the Exchange Act), in a single transaction or in a related series of transactions, by way of acquisition, merger, amalgamation, consolidation, transfer, conveyance or other business combination or purchase of beneficial ownership (within the meaning of Rule 13d-3 under the Exchange Act, or any successor provision) of more than 50% of the total voting power of the voting stock of LyondellBasell, other than by virtue of the imposition of a holding company, or the reincorporation of LyondellBasell in another jurisdiction, so long as the beneficial owners of the voting stock of LyondellBasell immediately prior to such transaction hold a majority of the voting power of the voting stock of such holding company or reincorporation entity immediately thereafter.

        Notwithstanding the foregoing, a transaction will not be deemed to involve a change of control under clause (2) above if (i) LyondellBasell becomes a direct or indirect wholly owned subsidiary of a holding company and (ii)(A) the direct or indirect holders of the voting stock of such holding company immediately following that transaction are substantially the same as the holders of LyondellBasell's voting stock immediately prior to that transaction or (B) immediately following that transaction no person (other than a holding company satisfying the requirements of this sentence) is the beneficial owner, directly or indirectly, of more than 50% of the voting stock of such holding company. The term "person," as used in this definition, has the meaning given thereto in Section 13(d)(3) of the Exchange Act.

        The definition of "change of control" includes a phrase relating to the direct or indirect sale, lease, transfer, conveyance or other disposition of "all or substantially all" of LyondellBasell's assets and the assets of LyondellBasell's subsidiaries, taken as a whole. Although there is a limited body of case law interpreting the phrase "substantially all," there is no precise, established definition of the phrase under applicable law. Accordingly, the applicability of the requirement that LYB International Finance II offer to repurchase the notes of a series as a result of a sale, lease, transfer, conveyance or other disposition of less than all of LyondellBasell's assets and the assets of LyondellBasell's subsidiaries, taken as a whole, to another person may be uncertain.

        Notwithstanding the foregoing, the disposition of a "disposed group" will not constitute a change of control pursuant to clause (1) of the definition thereof. See "Description of Debt Securities—Limitation on Mergers and Consolidations" in the accompanying prospectus.

        The occurrence of events that would constitute a change of control may also constitute an event of default under or require repurchase of LyondellBasell's, LYB International Finance's, or LYB International Finance II's other indebtedness. Future indebtedness of LyondellBasell or its subsidiaries may contain prohibitions on certain events that would constitute a change of control or require such indebtedness to be repurchased upon a change of control. Moreover, the exercise by the holders of their right to require LYB International Finance II to repurchase the notes of a series could cause a default under LyondellBasell's or LYB International Finance II's other indebtedness or credit facilities, even if the change of control itself does not, due to the financial effect of such repurchase on LyondellBasell or LYB International Finance II. Finally, LYB International Finance II's ability to

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repurchase the notes of a series upon a change of control triggering event with respect to such series of notes may be limited by its or LyondellBasell's then existing financial resources. There can be no assurance that sufficient funds will be available when necessary to make any required repurchases. See "Risk Factors—Risks Relating to the Notes—LYB International Finance II may not be able to fulfill its repurchase obligations in the event of a change of control triggering event."

        The provisions under the indenture relating to LYB International Finance II's obligation to make an offer to repurchase the notes of a series as a result of a change of control triggering event with respect to such series of notes may be waived or modified with the consent of the holders of a majority in aggregate principal amount of the notes of such series.

        "change of control triggering event" means the occurrence of both a change of control and a rating event.

        "investment grade rating" means a rating equal to or higher than Baa3 (or the equivalent) by Moody's and BBB- (or the equivalent) by S&P, and the equivalent investment grade credit rating from any replacement rating agency or rating agencies selected by LyondellBasell.

        "Moody's" means Moody's Investors Service, Inc. and its successors.

        "rating agencies" means (1) each of Moody's and S&P and (2) if either of Moody's or S&P ceases to rate the notes of the relevant series or fails to make a rating of the notes of such series publicly available for reasons outside of LyondellBasell's control, a "nationally recognized statistical rating organization" within the meaning of Section 3(a)(62) of the Exchange Act selected by LyondellBasell (as certified by a resolution of LyondellBasell's managing board) as a replacement agency for Moody's or S&P, or all of them, as the case may be.

        "rating event" means the rating on the notes of the applicable series is lowered by both of the two rating agencies and the notes of such series are rated below an investment grade rating by both of the two rating agencies, in any case on any day during the period (which period will be extended so long as the rating of the notes of such series is under publicly announced consideration for a possible downgrade by either of the rating agencies) commencing 60 days prior to the first public notice of the occurrence of a change of control or LyondellBasell's intention to effect a change of control and ending 60 days following consummation of such change of control.

        "S&P" means S&P Global Ratings, a division of S&P Global, Inc., and its successors.

        "voting stock" means, with respect to any specified "person" (as that term is used in Section 13(d)(3) of the Exchange Act) as of any date, the capital stock of such person that is at the time entitled to vote generally in the election of the board of directors of such person.

Certain Covenants

        Certain covenants in the indenture will limit LyondellBasell's ability and the ability of its subsidiaries to:

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create, incur or assume debt secured by liens;



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enter into sale and lease-back transactions; and



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merge, consolidate or transfer all or substantially all of LyondellBasell's or LYB International Finance II's assets.

        For a description of these covenants, see "Description of Debt Securities—Limitation on Mergers and Consolidations" and "—Restrictive Covenants" in the accompanying base prospectus.

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Redemption for Changes in Taxes

        LYB International Finance II may redeem the notes of a series, in whole but not in part, at its discretion at any time upon giving not less than 10 nor more than 60 days' prior notice (which notice will be irrevocable), at a redemption price equal to 100% of the principal amount thereof, together with accrued and unpaid interest, if any, to the date fixed by LYB International Finance II for redemption and all additional amounts (if any) then due and which will become due on that date as a result of the redemption or otherwise (subject to the right of holders of the notes on the relevant record date to receive interest when due and additional amounts (if any) in respect thereof), if on the next date on which any amount would be payable in respect of the notes or the guarantees of the notes, LYB International Finance II or LyondellBasell, as the case may be, is or would be required to pay additional amounts (as described below under "—Additional Amounts"), and LYB International Finance II and LyondellBasell cannot avoid any such payment obligation by taking reasonable measures available, and the requirement arises as a result of:

        (1)   any change in, or amendment to, the laws or treaties (or any regulations, or rulings promulgated thereunder) of a Tax Jurisdiction affecting taxation which change or amendment becomes effective on or after the issue date (or, if a jurisdiction becomes a Tax Jurisdiction after the issue date, the date on which such jurisdiction became a Tax Jurisdiction under the indenture); provided, however, in the case of a successor entity of LYB International Finance II or LyondellBasell, the change or amendment must become effective after the date that such successor entity first makes payment on the notes or the guarantees; or

        (2)   any change in, or amendment to, the existing official position or the introduction of an official position regarding the application, administration or interpretation of such laws, treaties, regulations or rulings of a Tax Jurisdiction (including a holding, judgment or order by a court of competent jurisdiction or a change in published practice), which change, amendment application or interpretation becomes effective on or after the issue date (or, if a jurisdiction becomes a Tax Jurisdiction after the issue date, the date on which such jurisdiction became a Tax Jurisdiction under the indenture); provided, however, in the case of a successor entity of LYB International Finance II or LyondellBasell, the change or amendment must become effective after the date that such successor entity first makes payment on the notes or the guarantees.

        LYB International Finance II will not give any such notice of redemption earlier than 90 days prior to the earliest date on which LYB International Finance II or LyondellBasell, as the case may be, would be obligated to make such payment or withholding if a payment were then due, and at the time such notice is given, the obligation to pay additional amounts must remain in effect. Prior to the publication or, where relevant, mailing of any notice of redemption pursuant to the foregoing, LYB International Finance II will deliver to the trustee an opinion of counsel to the effect that there has been such change or amendment that would entitle LYB International Finance II to redeem the notes of a series under the indenture. In addition, before LYB International Finance II publishes or mails notice of redemption of the notes of a series as described above, it will deliver to the trustee an officer's certificate to the effect that it or LyondellBasell cannot avoid the obligation to pay additional amounts by taking reasonable measures available to it.

        The trustee will accept such officer's certificate and opinion of counsel as sufficient evidence of the existence and satisfaction of the conditions precedent as described above, in which event it will be conclusive and binding on the holders of the notes of the relevant series.

        "Tax Jurisdiction" means any jurisdiction in which LYB International Finance II or LyondellBasell (or a successor to either entity as issuer or guarantor) is incorporated or resident for tax purposes or any department or political subdivision thereof or therein or any jurisdiction from or through which payment with respect to the notes or the guarantees of the notes is made or deemed to be made by LYB International Finance II or LyondellBasell, in each case.

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Additional Amounts

        All payments made under or with respect to the notes and the guarantees of the notes of each series will be made free and clear of and without withholding or deduction for, or on account of, any present or future taxes imposed or levied by or on behalf of any applicable Tax Jurisdiction unless the withholding or deduction of such taxes is then required by law. If any deduction or withholding for, or on account of, any taxes imposed or levied by or on behalf of any applicable Tax Jurisdiction, will at any time be required to be made from any payments made under or with respect to the notes or the guarantees, including, without limitation, payments of principal, redemption price, purchase price, interest or premium, LYB International Finance II or LyondellBasell, as the case may be, will pay such additional amounts as may be necessary in order that the aggregate net amounts received in respect of such payments by the holders of the notes of such series in respect of the notes or the guarantees (including additional amounts) after such withholding, deduction or imposition will equal the respective amounts that would have been received in respect of such payments in the absence of such withholding or deduction; provided that no additional amounts will be payable with respect to:

        (1)   any note presented for payment in the United Kingdom or any other EU member state;

        (2)   any taxes that would not have been imposed but for the holder's or beneficial owner's present or former connection with the relevant Tax Jurisdiction or but for any such connection on the part of a partner, beneficiary, settlor or shareholder of such holder or beneficial owner (other than any connection resulting from the acquisition, ownership, holding or disposition of the notes, the receipt of payments thereunder or under the guarantees and/or the exercise or enforcement of rights under the notes or the guarantees);

        (3)   any taxes that are imposed or withheld as a result of the failure of the holder of the notes of the relevant series or beneficial owner of the notes of such series to comply with any reasonable written request, made to that holder or beneficial owner in writing at least 30 days before any such withholding or deduction would be payable, by LYB International Finance II or LyondellBasell to provide timely and accurate information concerning the nationality, residence or identity of such holder or beneficial owner or to make any valid and timely declaration or similar claim or satisfy any certification, information or other reporting requirement, which is required or imposed by a statute, treaty, regulation or administrative practice of the relevant Tax Jurisdiction as a precondition to any exemption from or reduction in all or part of such taxes to which such holder is entitled;

        (4)   any note presented for payment more than 30 days after the relevant payment is first made available for payment to the holder (except to the extent that the holder would have been entitled to additional amounts had the note been presented on the last day of such 30-day period);

        (5)   any payment of principal or interest on the notes of the relevant series made to any holder who is a fiduciary or partnership or any person other than the sole beneficial owner of such payment, to the extent that such payment would be required to be included in the income under the laws of the Tax Jurisdiction, for tax purposes, of a beneficiary or settlor with respect to such fiduciary, a member of such a partnership or the beneficial owner of such payment who would not have been entitled to the additional amounts had such beneficiary, settlor, member or beneficial owner been the actual holder of the notes of such series;

        (6)   any estate, inheritance, gift, sales, transfer, personal property or similar taxes;

        (7)   any taxes payable other than by deduction or withholding from payments under, or with respect to, the notes of the relevant series or with respect to the guarantee of such notes;

        (8)   any taxes imposed by the United States or any political subdivision thereof or tax authority therein;

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        (9)   any taxes, assessments or other governmental charge imposed by the United States or by a taxing authority in the United States under Section 1471 through 1474 of the Code (or any amended or successor provisions), any current or future regulations or official interpretations thereof, any agreement entered into pursuant to Section 1471(b) of the Code or any fiscal or regulatory legislation, rules or practices adopted pursuant to any intergovernmental agreement entered into in connection with the implementation of such sections of the Code; or

        (10) any combination of items (1) through (9) above.

        If LYB International Finance II or LyondellBasell, as the case may be, becomes aware that it will be obligated to pay additional amounts pursuant to this covenant with respect to any payment under or with respect to the notes or the guarantee of the notes of a series, LYB International Finance II or LyondellBasell, as the case may be, will deliver to the trustee on a date that is at least 30 days prior to the date of that payment (unless the obligation to pay such additional amounts arises after the 30th day prior to that payment date, in which case LYB International Finance II or LyondellBasell, as the case may be, shall notify the trustee promptly thereafter) an officer's certificate of LYB International Finance II or LyondellBasell, as the case may be, stating the fact that such additional amounts will be payable pursuant to this covenant and the amount estimated to be so payable. Such officer's certificate must also set forth any other information reasonably necessary to enable the paying agents to pay such additional amounts to holders of the notes of such series on the relevant payment date. The trustee shall be entitled to rely solely on such officer's certificate as conclusive proof that such payments are necessary. LYB International Finance II or LyondellBasell, as the case may be, will provide the trustee with documentation reasonably satisfactory to the trustee evidencing the payment of additional amounts.

        LYB International Finance II or LyondellBasell, as the case may be, will make all withholdings and deductions required by law and will remit the full amount deducted or withheld to the relevant tax authority in accordance with applicable law with respect to payments in respect of the notes or the guarantees. Upon request, LYB International Finance II or LyondellBasell, as the case may be, will provide to the trustee an official receipt or, if official receipts are not obtainable, other documentation reasonably satisfactory to the trustee evidencing the payment of any taxes so deducted or withheld. Upon request, copies of those receipts or other documentation, as the case may be, will be made available by the trustee to the holders of the notes.

        The obligations in this covenant will survive any transfer by a holder or beneficial owner of its notes and will apply mutatis mutandis to any jurisdiction in which any successor person to LYB International Finance II or LyondellBasell is incorporated or resident for tax purposes or any jurisdiction from or through which such person makes any payment in respect of the notes or the guarantees of such notes and any department or political subdivision thereof or therein.

Future Issuances of Notes

        LYB International Finance II may from time to time, without notice or the consent of the registered holders of either series of notes, create and issue additional notes of such series ranking identical to the notes of such series described in this prospectus supplement (or in all respects except for the issue date, the public offering price, the initial interest payment date, if applicable, and the payment of interest accruing prior to the issue date of such additional notes), so that such additional notes shall be consolidated and form a single series with the related series of notes offered hereby and shall have the same terms as to status, redemption or otherwise as the notes offered hereby; provided, however, that if such additional notes are not fungible with the related series of notes offered hereby for U.S. federal income tax purposes, such additional notes will not have the same "CUSIP" number, "ISIN" or common code (as applicable) as the same series of notes offered hereby. There will be no restrictions in the indenture or either series of notes on the amount of additional notes that LYB

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International Finance II might issue in the future. We may at any time purchase notes in the open market or otherwise at any price.

Book-Entry; Delivery and Form; Global Notes

        We have obtained the information in this section concerning Clearstream Banking, S.A. ("Clearstream") and Euroclear Bank SA/NV, or its successor, as operator (the "Euroclear Operator") of the Euroclear System ("Euroclear") (together, Clearstream and Euroclear are referred to herein as the "ICSDs") and their book-entry systems and procedures from sources that we believe to be reliable. We take no responsibility for an accurate portrayal of this information. In addition, the description of the clearing systems in this section reflects our understanding of the rules and procedures of the ICSDs as they are currently in effect. Those clearing systems could change their rules and procedures at any time.

        The notes will initially be represented by the Global Notes. The notes, when issued in global form, are intended to be eligible to be pledged as collateral in European central banking and monetary operations and to be held under the "new safekeeping structure," or NSS. The Global Notes will be deposited with, or on behalf of, a Common Safekeeper for Euroclear and Clearstream and issued to and registered in the name of a nominee of the Common Safekeeper. Except as set forth below, the Global Notes may be transferred, in whole and not in part, only to another nominee of the ICSDs. Investors may hold their beneficial interests in the Global Notes directly through an ICSD if they have an account with an ICSD or indirectly through organizations which have accounts with the ICSDs.

        The ICSDs hold securities of institutions that have accounts with the ICSDs ("participants") and to facilitate the clearance and settlement of securities transactions among their participants in such securities through electronic book-entry changes in accounts of the participants, thereby eliminating the need for physical movement of securities certificates. The ICSDs' participants include securities brokers and dealers (which may include the underwriters), banks, trust companies, clearing corporations and certain other organizations. Access to each ICSD's book-entry system is also available to others such as banks, brokers, dealers and trust companies ("indirect participants") that clear through or maintain a custodial relationship with a participant, whether directly or indirectly.

        We expect that pursuant to procedures established by the ICSDs, upon the deposit of the Global Notes with the Common Safekeeper, the ICSDs will credit, on their book-entry registration and transfer systems, the interest in the notes represented by such Global Notes to the accounts of participants. The accounts to be credited shall be designated by the underwriters of the notes. Ownership of beneficial interests in the Global Notes will be limited to participants or persons that may hold interests through participants. Ownership of beneficial interests in the Global Notes will be shown on, and the transfer of those ownership interests will be effected only through, records maintained by the ICSDs (with respect to participants' interests) and such participants and indirect participants (with respect to the owners of beneficial interests in the Global Notes other than participants). The laws of some jurisdictions may require that certain purchasers of securities take physical delivery of such securities in definitive form.

        Although the ICSDs customarily operate the foregoing procedures in order to facilitate transfers of interests in the Global Notes among participants or indirect participants of the ICSDs, they are under no obligation to perform or continue to perform such procedures, and such procedures may be discontinued at any time. Neither we nor the trustee will have any responsibility or liability for the performance by either ICSD or its participants or indirect participants of their respective obligations under the rules and procedures governing their operations.

        Except as provided below, owners of beneficial interests in the notes will not be entitled to have the notes registered in their names, will not receive or be entitled to receive physical delivery of the notes in definitive form and will not be considered the owners or holders of the notes under the

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indenture, including for purposes of receiving any reports delivered by us or the trustee pursuant to the indenture. Accordingly, in the event an owner of a beneficial interest in the Global Notes desires to take any action that the nominee of the Common Safekeeper, as the holder of the Global Notes, is entitled to take, the Common Safekeeper will authorize the participants to take such action, and that the participants will authorize beneficial owners owning through such participants to take such action or would otherwise act upon the instructions of beneficial owners owning through them.

        All payments on notes represented by the Global Notes registered in the name of the nominee of the Common Safekeeper and held by the Common Safekeeper will be made to the ICSDs or the nominee of the Common Safekeeper, as the case may be, as the registered owner and holder of the Global Notes.

        We have been advised by Clearstream and Euroclear, respectively, as follows:

Clearance and Settlement Procedures

        We expect that the ICSDs, upon receipt of any payment on the Global Notes, will credit participants' accounts with payments in amounts proportionate to their respective beneficial interests in the Global Notes as shown on the records of the ICSDs. We also expect that payments by participants or indirect participants to owners of beneficial interest in the Global Notes held through such participants or indirect participants will be governed by standing instructions and customary practices and will be the responsibility of such participants or indirect participants. We will not 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 for any notes or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests or for any other aspect of the relationship between the ICSDs and their participants or indirect participants or the relationship between such participants or indirect participants and the owners of beneficial interests in the Global Notes owning through such participants or indirect participants. You should be aware that investors will only be able to make and receive deliveries, payments and other communications involving the notes through the ICSDs on days when those systems are open for business. Those systems may not be open for business on days when banks, brokers and other institutions are open for business in the United States.

Certificated Notes

        If:

•

we have been notified that Euroclear or Clearstream (or any additional or alternative clearing system approved by LYB International Finance II, the trustee and the paying agent on behalf of which the Global Notes may be held) has been closed for business for a continuous period of 14 days (other than by reason of holidays, statutory or otherwise) or has announced an intention permanently to cease business or does in fact do so; or



•

an event of default has occurred and is continuing and the registrar has received a request from Euroclear or Clearstream;

then, upon surrender by an ICSD of the Global Notes, certificated notes will be issued to each person that the ICSD identifies as the beneficial owner of the notes represented by the Global Notes. Upon the issuance of certificated notes, the trustee is required to register the certificated notes in the name of that person or persons, or their nominee, and cause the certificated notes to be delivered thereto.

        None of LyondellBasell, LYB International Finance II or the trustee will be liable for any delay by an ICSD or any participant or indirect participant in the ICSD in identifying the beneficial owners of the related notes and each of those persons may conclusively rely on, and will be protected in relying

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on, instructions from the ICSD for all purposes, including with respect to the registration and delivery, and the respective principal amounts, of the notes to be issued.

Eurosystem Eligibility

        The notes are intended to be held in a manner which would allow Eurosystem eligibility. This simply means that the notes are intended upon issue to be deposited with one of the ICSDs as Common Safekeeper, and registered in the name of a nominee of one of the ICSDs acting as Common Safekeeper, and does not necessarily mean that the notes will be recognized as eligible collateral for Eurosystem monetary policy and intraday credit operations by the Eurosystem either upon issue or at any or all times during their life. Such recognition will depend upon the European Central Bank being satisfied that Eurosystem eligibility criteria have been met.

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TAX CONSEQUENCES

DESCRIPTION OF CAPITAL STOCK

General

        The following descriptions are summaries of material terms of LyondellBasell's ordinary shares, with a par value of four eurocents (€0.04) each, LyondellBasell's Articles of Association (which we refer to in this section as our Articles of Association) and Dutch law. The full text of our current Articles of Association has been filed with the SEC and is available, in Dutch and English, at our registered office in Rotterdam during regular business hours and is also available, in English, on our website.

Ordinary Shares

        LyondellBasell's authorized share capital is fifty-one million euro (€51,000,000), consisting of one billion two hundred seventy-five million (1,275,000,000) ordinary shares, each with a par value of four eurocents (€0.04). As of February 19, 2019, there were 373,058,535 ordinary shares outstanding, not including 27,151,745 ordinary shares held in treasury.

        The description of LyondellBasell's ordinary shares is contained in our Registration Statement on Form 10 filed with the SEC pursuant to Section 12 of the Exchange Act on April 28, 2010, as amended, which is incorporated by reference into this prospectus.

Voting and Approval Rights

        Generally, each shareholder is entitled to one vote for each ordinary share held on every matter submitted to a vote of shareholders, including the annual election of members of the Board of Directors (the "Board"). There are no cumulative voting rights. Pursuant to Dutch law and our Articles of Association, the nomination of a director to our Board is binding on shareholders unless two-thirds of shareholders, representing at least half of issued share capital, vote against the nominee.

        Unless otherwise required by our Articles of Association or Dutch law, matters submitted for a vote at a general meeting of shareholders require the approval of a majority of the votes cast at the general meeting. Pursuant to Dutch law and our Articles of Association, shareholders have the right to approve decisions of the Board relating to (i) the transfer of all or substantially all our enterprise by way of a share or asset sale, consolidation or merger or otherwise, (ii) the entering into or termination of a long-lasting commercial relationship that is of essential importance to our business and (iii) the acquisition or disposition of shares or assets with a value of at least one-third of our consolidated asset value.

        There are no laws currently in effect in The Netherlands or provisions in our Articles of Association limiting the rights of non-resident investors to hold or vote ordinary shares.

Dividends and Distributions

        Pursuant to our Articles of Association, the Board may determine to allocate amounts to our reserves up to the amount of our annual profits. Out of our share premium reserve and other reserves available for shareholder distributions under Dutch law, the general meeting of shareholders may declare distributions upon a proposal of the Board. We cannot pay dividends if the payment would reduce our shareholders' equity below the aggregate par value of our outstanding ordinary shares, plus reserves (if any) required to be maintained by law. The Board may, subject to certain statutory provisions, distribute one or more interim dividends or other interim distributions before the accounts for any year have been approved and adopted at a general meeting of shareholders, in anticipation of the final dividend or final distribution. Rights to dividends and distributions that have not been collected within five years after the date on which they first became due and payable revert to LyondellBasell.

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        The payment of dividends or distributions is subject to the requirements of Dutch law and the discretion of our shareholders (in the case of annual dividends) and our Board. The declaration of any cash dividends and, if declared, the amount of any such dividends, will depend upon general business conditions, our financial condition, our earnings and cash flow, our capital requirements, financial covenants and other contractual restrictions on the payment of dividends or distributions. There can be no assurance that any dividends or distributions will be declared or paid in the future. Any future cash dividends or distributions will be paid in U.S. dollars.

Shareholder Meetings

        Each shareholder and certain other parties designated under Dutch law will be permitted, either personally or through an attorney authorized in writing, to attend the general meeting of shareholders, to address said meetings and to exercise voting rights, subject to certain provisions of Dutch law and our Articles of Association.

        Our general meetings of shareholders will be held in The Netherlands at least annually, within six months after the close of each financial year. Extraordinary general meetings of shareholders may be held as often as the Board deems necessary, or as otherwise provided for pursuant to Dutch law. One or more shareholders representing in the aggregate at least 10% of the issued share capital can request the Board to convene a general meeting of shareholders. In such case, the Board is required to publish a convening notice for such a general meeting of shareholders within four weeks of receipt from such shareholders of (i) a specified agenda for such general meeting of shareholders and, (ii) in the sole discretion of the Board, compelling evidence of the number of shares held by such shareholder or shareholders. If such meeting is not held within six weeks of our receipt of such request, the shareholders requesting a meeting may petition a court in The Netherlands for an order directing the holding of such meeting; the court may order the holding of such a meeting if the persons requesting the meeting can demonstrate that they have a sufficient interest in holding a meeting with the agenda requested by them. In addition, affiliates of Access Industries, one of our shareholders, can require the Board to convene a general meeting of shareholders, for the purpose of allowing for the appointment of one or more of its director nominees under certain circumstances, for so long as it holds, together with its affiliates, at least 5% of the issued share capital.

        One or more shareholders representing solely or jointly at least 1% of the issued share capital can request the Board to place a matter on the agenda, provided that the Board has received such request at least 60 days prior to the date of the general meeting of shareholders concerned.

Election and Tenure of Directors

        Our Board includes both executive and non-executive members. The executive members of our Board are charged with managing our day-to-day affairs. The non-executive members of our Board are charged with the supervision of the executive Board member(s) and our general course of affairs.

        The Board shall determine its size; provided that the Board shall consist of at least nine members, including at least one executive Board member who will hold the title of CEO, and the number of non-executive Board members shall at all times exceed the number of executive Board members.

        The general meeting of shareholders appoints the member(s) of the Board, subject to the terms of any binding nomination agreements; providedthat the Board may provide for temporary replacements in the event of a vacancy or the inability to act of a Board member.

        We have entered into a binding nomination agreement with affiliates of Access Industries pursuant to which we agreed that (i) if it, together with its affiliates, owns 18% or more of our outstanding ordinary shares, it will have the right to nominate three non-executive members of the Board; (ii) if it, together with its affiliates, owns at least 12% but less than 18% of our outstanding ordinary shares, it

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will have the right to nominate two non-executive members of the Board; and (iii) if it, together with its affiliates, owns at least 5% but less than 12% of our outstanding ordinary shares, it will have the right to nominate one non-executive member of the Board. The general meeting of shareholders may render such nomination non-binding by means of a resolution adopted by at least two-thirds of the valid votes cast, representing more than half of the issued capital. As of February 19, 2019, three of the members of our Board were nominated in accordance with this agreement.

        The general meeting of shareholders may dismiss, or suspend for a period of up to three months, a member of the Board by a resolution adopted by at least two-thirds of the votes cast in a meeting where at least half of the issued share capital is represented. If the general meeting of shareholders has suspended a member of the Board, the general meeting of shareholders shall within three months after the suspension has taken effect resolve either to dismiss such relevant member, or to terminate or continue the suspension, failing which the suspension shall lapse.

        Each member of the Board serves a one-year term and there is no limit to the number of times a member of the Board can be reappointed.

        Subject to our Articles of Association, the Board may adopt rules and regulations governing its internal proceedings of each such constituency, including rules relating to voting on nominations of directors, board composition and governance.

Issuance of Ordinary Shares/Pre-emptive Rights

        Our Articles of Association provide that our Board has the authority to issue shares if authorized by resolution of our shareholders. No such authorization is currently in place. Shareholders may resolve to issue shares on a proposal of the Board in the absence of a Board authorization.

        Under Dutch law and our Articles of Association, every holder of ordinary shares will have a preemptive right in the proportion that the aggregate amount of its ordinary shares bears to the total amount of shares outstanding. The preemptive right may be restricted or excluded by a resolution of the Board if the Board is the competent body to issue shares. Otherwise, preemptive rights may be restricted or excluded by shareholders on a proposal of the Board. A holder of ordinary shares will not have a preemptive right to shares which are being issued against contribution other than in cash; to ordinary shares which will be issued to our employees or employees of one of our group companies; and to ordinary shares which will be issued as a result of merger or demerger.

Repurchase of Ordinary Shares

        The shareholders may delegate to the Board the authority, subject to certain restrictions contained in Dutch law and our Articles of Association, to cause us to acquire, for consideration, our own fully paid ordinary shares. Such authorization may not be granted for a period exceeding 18 months. In the authorization, the general meeting of shareholders shall determine how many shares thereof may be acquired, the manner in which they may be acquired and between what limits the price for such ordinary shares shall be.

        The authorization will not be required for the acquisition of ordinary shares by us for transfer to our employees in accordance with an employee share plan.

        At our 2018 general meeting of shareholders, shareholders granted authority to the Board to repurchase up to 10% of our issued share capital until December 1, 2019 on the open market, through privately negotiated repurchases, in self-tender offers, or through accelerated repurchase arrangements, at prices ranging up to 110% of the market price at the time of the transaction (or, in the case of an accelerated repurchase arrangement, 110% of the market price over the term of the arrangement).

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Capital Reduction

        Upon proposal by the Board, the general meeting of shareholders may reduce our issued share capital by cancellation of ordinary shares held by us, subject to certain statutory provisions. However, if less than one half of the issued share capital is present at the meeting, the general meeting of shareholders may only adopt a resolution for capital reduction with a majority of at least two-thirds of the votes cast. As of February 19, 2019, we held 27,151,745 shares in our treasury account and we cancelled 178,229,883 shares effective September 5, 2018.

Amendment of Our Articles of Association

        Our Articles of Association may be amended, on the proposal of the Board, by a majority of the votes cast at a general meeting of shareholders; provided that such proposal is stated in the notice for the general meeting and a complete copy of the proposed amendment is filed at our office so that it may be inspected prior to and during the meeting.

DESCRIPTION OF DEBT SECURITIES

        The debt securities of LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III covered by this prospectus will be the general unsecured obligations of LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III, respectively. The debt securities of LYB International Finance, LYB International Finance II and LYB International Finance III will be fully and unconditionally guaranteed by LyondellBasell. The debt securities of LyondellBasell may be fully and unconditionally guaranteed by LYB International Finance, LYB International Finance II or LYB International Finance III. LyondellBasell will issue senior debt securities under an indenture between LyondellBasell, as issuer, and Wells Fargo Bank, N.A., as trustee, dated as of March 5, 2015 (the "LyondellBasell Indenture"). LYB International Finance will issue senior debt securities fully and unconditionally guaranteed by LyondellBasell on a senior unsecured basis under an indenture among LYB International Finance, as issuer, LyondellBasell as guarantor, and Wells Fargo Bank, N.A., as trustee, dated as of July 16, 2013 (the "LYB International Finance Indenture"). LYB International Finance II will issue senior debt securities fully and unconditionally guaranteed by LyondellBasell on a senior unsecured basis under an indenture among LYB International Finance II, as issuer, LyondellBasell as guarantor, and Deutsche Bank Trust Company Americas, as trustee, dated as of March 2, 2016 (the "LYB International Finance II Indenture"). LYB International Finance III will issue senior debt securities fully and unconditionally guaranteed by LyondellBasell on a senior unsecured basis under an indenture to be entered into among LYB International Finance III, as issuer, LyondellBasell as guarantor, and Wells Fargo Bank, N.A., as trustee (the "LYB International Finance III Indenture"). The LyondellBasell Indenture, LYB International Finance Indenture and LYB International Finance II Indenture are, and the LYB International Finance III Indenture will be, substantially identical except with regards to the entities that will issue and guarantee, if any, the debt securities governed by such indenture.

        We have summarized certain material provisions of the indentures, the debt securities and the guarantees below. This summary is not complete. We have filed the indentures (or their forms) with the SEC as exhibits to the registration statement of which this prospectus forms a part, and you should read the indentures for provisions that may be important to you. Please read "Where You Can Find More Information."

        In this summary description of the debt securities, unless we state otherwise or the context clearly indicates otherwise, all references to "LyondellBasell" mean LyondellBasell, all references to "LYB

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International Finance" mean LYB International Finance only, all references to "LYB International Finance II" mean LYB International Finance II only and all references to "LYB International Finance III" mean LYB International Finance III only.

        General.    The indentures do not limit the amount of debt securities that LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III may issue under the indentures, and do not limit the amount of other unsecured debt or securities that LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III may issue. LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III may issue debt securities under the indentures from time to time in one or more series, each in an amount authorized prior to issuance.

        Terms.    The prospectus supplement relating to any series of debt securities being offered will include specific terms relating to the offering. These terms will include some or all of the following:

•

the price at which LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III will issue the debt securities;



•

the title of the debt securities;



•

the total principal amount of the debt securities;



•

in the case of debt securities issued by LyondellBasell, whether the payment of principal and interest on the debt securities is guaranteed and, if so, the terms of the guarantee;



•

whether LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III will initially issue the debt securities in individual certificates to each holder or in the form of temporary or permanent global securities held by a depositary on behalf of holders;



•

the date or dates on which the principal of and any premium on the debt securities will be payable;



•

any interest rate, the date from which interest will accrue, interest payment dates and record dates for interest payments;



•

whether and under what circumstances LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III will pay any additional amounts with respect to the debt securities;



•

the place or places where payments on the debt securities will be payable;



•

any provisions for optional redemption or early repayment;



•

any sinking fund or other provisions that would require LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III to redeem, purchase or repay the debt securities;



•

the denominations in which LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III will issue the debt securities if other than $2,000 and integral multiples of $1,000;



•

if payments on the debt securities will be payable in foreign currency or currency units or another form and if payments will be payable by reference to any index or formula;



•

any provisions for additional tax amounts or redemption for changes in taxes;



•

the portion of the principal amount of debt securities that will be payable if the maturity is accelerated, if other than the entire principal amount;

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•

any additional means of defeasance of the debt securities, any additional conditions or limitations to defeasance of the debt securities or any changes to those conditions or limitations;



•

any changes or additions to the events of default or covenants described in this prospectus and whether such changes or additions are subject to covenant defeasance;



•

any restrictions or other provisions relating to the transfer or exchange of debt securities;



•

any terms for the conversion or exchange of the debt securities for other securities of LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III or any other entity; and



•

any other terms of the debt securities which terms shall not adversely affect any prior series of debt securities.

        LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III may sell the debt securities at a discount, which may be substantial, below their stated principal amount. These debt securities may bear no interest or interest at a rate that at the time of issuance is below market rates. If these debt securities are sold, we will describe in the prospectus supplement any material United States federal income tax consequences and other special considerations.

        If any of the debt securities are sold for any foreign currency or currency unit or if payments on the debt securities are payable in any foreign currency or currency unit, we will describe in the prospectus supplement the restrictions, elections, tax consequences, specific terms and other information relating to those debt securities and the foreign currency or currency unit.

        Limitation on Mergers and Consolidations.    The indentures generally permit a consolidation or merger involving LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III. They also permit LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III to sell, lease, convey, assign, transfer or otherwise dispose of all or substantially all of their assets. Each of LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III has agreed, however, that it will not consolidate with or merge into any entity (other than, with respect to LYB International Finance, LYB International Finance II and LYB International Finance III, LyondellBasell), or sell, lease, convey, assign, transfer or otherwise dispose of, in any transaction or series of transactions, all or substantially all of its property and assets to any person (other than, with respect to LYB International Finance, LYB International Finance II and LYB International Finance III, LyondellBasell), unless

•

either (i) it is the continuing entity or (ii) the resulting entity is organized under the laws of the United States, any state in the United States, the District of Columbia, Canada, any province of Canada or any state which was a member of the European Union on December 31, 2003 (other than Greece) and, in each case expressly assumes by a supplemental indenture the performance of its covenants and obligations under the applicable indenture and, in the case of LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III as the issuer, the due and punctual payment on the debt securities or, in the case of LyondellBasell with respect to the debt securities of LYB International Finance, LYB International Finance II or LYB International Finance III or LYB International Finance, LYB International Finance II or LYB International Finance III with respect to the debt securities of LyondellBasell, the performance of the related guarantee; and



•

immediately after giving effect to such transaction or series of transactions, no default or event of default occurred and is continuing or would result therefrom.

        LyondellBasell is also permitted to sell, assign, transfer, lease, convey or otherwise dispose, in one or more related transactions, of assets constituting the capital stock or all or part of the assets of any

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subsidiary, division or line of business or group of such subsidiaries, divisions or lines of business ("disposed group") if such disposed group (i) generated Consolidated EBITDA that was less than 40% of the Consolidated EBITDA of LyondellBasell in (a) the most recently completed four quarters or fiscal year for which financial statements are required to be delivered pursuant to the indenture and (b) each of the last three completed fiscal years of LyondellBasell for which financial statements are required to be delivered pursuant to the indenture and (ii) has total assets with a value that is less than 40% of the total value of the consolidated assets of LyondellBasell and its subsidiaries, as determined in accordance with GAAP as of the last date of the latest period for which financial statements are required to be delivered pursuant to the indenture; provided that such disposition otherwise complies with the indenture.

        Upon any transaction of the type described in and effected in accordance with this covenant, the resulting entity will succeed to and be substituted for LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, and may exercise all of LyondellBasell's, LYB International Finance's, LYB International Finance II's or LYB International Finance III's rights and powers under the indentures and the debt securities with the same effect as if the resulting entity had been named as LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, in the indentures. In the case of any asset transfer or disposition other than a lease, when the resulting entity assumes all of LyondellBasell's, LYB International Finance's, LYB International Finance II's or LYB International Finance III's obligations and covenants under the applicable indenture and the debt securities, LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, will be relieved of all such obligations.

        Events of Default.    Unless we inform you otherwise in the applicable prospectus supplement, the following are events of default with respect to a series of debt securities:

•

failure to pay interest or any additional amounts on any debt securities of that series for 30 days when due;



•

failure to pay principal of or any premium on any debt securities of that series when due;



•

failure to make or deposit any sinking fund payment for that series for 30 days when due;



•

failure to comply with any covenant or agreement in that series of debt securities or the applicable indenture (other than the events of default above or an agreement or covenant that has been included in the applicable indenture solely for the benefit of other series of debt securities) for 90 days after written notice by the trustee or by the holders of at least 25% in principal amount of the outstanding debt securities issued under that indenture that are affected by that failure;



•

in the case of LYB International Finance, LYB International Finance II and LYB International Finance III debt securities, the related guarantee of LyondellBasell ceases to be in full force and effect with respect to the debt securities of such series (except as contemplated by the terms thereof) and such default continues for 10 days;



•

specified events involving bankruptcy, insolvency or reorganization of LyondellBasell and, with respect to LYB International Finance's, LYB International Finance II's or LYB International Finance III's debt securities, LyondellBasell, or LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable; and



•

any other event of default provided for that series of debt securities for 90 days after written notice by the trustee or by the holders of at least 25% in principal amount of the outstanding debt securities issued under the applicable indenture that are affected by that failure.

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        A default under one series of debt securities will not necessarily be a default under any other series. If a default or event of default for any series of debt securities occurs, is continuing and is known to the trustee, the trustee will notify the holders of the applicable series of debt securities within 90 days after it becomes known to the trustee. The trustee may withhold notice to the holders of the debt securities of any series of any default or event of default, except in any payment on the debt securities of such series, if the trustee in good faith determines that withholding notice is in the interests of the holders of those debt securities.

        If an event of default for any series of debt securities occurs and is continuing, the trustee or the holders of at least 25% in principal amount of the outstanding debt securities of the series affected by the default (or, in the case of the event of default described in the fourth bullet above, 25% in principal amount of all debt securities issued under the applicable indenture that are affected by the default, voting as one class) may declare the principal of and all accrued and unpaid interest on those debt securities to be due and payable immediately. If an event of default relating to certain events of bankruptcy, insolvency or reorganization of us occurs, the principal of and accrued and unpaid interest on all the debt securities issued under that indenture will become immediately due and payable without any action on the part of the trustee or any holder. At any time after a declaration of acceleration has been made, the holders of a majority in principal amount of the outstanding debt securities of the series affected by the event of default (other than an event of default related to the non-payment of principal of or premium or interest on or any additional amounts) may in some cases rescind this accelerated payment requirement and its consequences.

        A holder of a debt security of any series issued under an indenture may pursue any remedy under that indenture only if:

•

the holder gives the trustee written notice of a continuing event of default with respect to that series;



•

the holders of at least 25% in principal amount of the then outstanding debt securities of that series make a written request to the trustee to pursue the remedy;



•

the holders offer to the trustee indemnity satisfactory to the trustee against any loss, liability or expense;



•

the trustee does not comply with the request within 60 days after receipt of the request and offer of indemnity; and



•

during that 60-day period, the holders of a majority in principal amount of the debt securities of that series do not give the trustee a direction inconsistent with the request.

        This provision does not, however, affect the right of a holder of a debt security to sue for enforcement of any overdue payment.

        In most cases, the trustee will be under no obligation to exercise any of its rights or powers under an indenture at the request or direction of any of the holders of a series of debt securities unless those holders have offered to the trustee indemnity satisfactory to it. Subject to this provision for indemnification, holders of a majority in principal amount of the outstanding debt securities of a series (or of all debt securities issued under an indenture that are affected, voting as one class) generally may direct the time, method and place of:

•

conducting any proceeding for any remedy available to the trustee; or



•

exercising any trust or power conferred on the trustee relating to or arising as a result of an event of default.

        If an event of default occurs and is continuing, the trustee will be required to use the degree of care and skill of a prudent person in the conduct of his own affairs.

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        Each indenture requires LyondellBasell, LYB International Finance, LYB International Finance II and LYB International Finance III, as applicable, to file each year with the trustee a written statement as to their compliance with the covenants contained in the indenture.

        Modification, Waiver and Meetings.    Each indenture may be amended or supplemented with the consent of the majority in principal amount of the outstanding debt securities of all series issued under that indenture that are affected by the amendment or supplement (voting as one class). Without the consent of the holder of each debt security affected, however, no modification may:

•

reduce the amount of debt securities of the relevant series whose holders must consent to an amendment, supplement or waiver;



•

reduce the rate of or change the time for payment of interest on the debt securities;



•

reduce the principal of, any premium on or any mandatory sinking fund payment with respect to the debt securities or change their stated maturity;



•

reduce any premium payable on the redemption of the debt security or change the time at which the debt securities may or must be redeemed;



•

change any obligation to pay additional amounts on the debt securities;



•

make payments on the debt securities payable in currency other than as originally stated in the debt securities;



•

impair the holder's right to institute suit for the enforcement of any payment on or with respect to the debt securities;



•

make any change in the percentage of principal amount of debt securities of the relevant series for a waiver of default or make any change in the provisions related to the rights of holders to receive payment or in these bullets regarding modification without the consent of holders;



•

waive a continuing default or event of default regarding any non-payment of principal of or premium or interest on or any additional amounts with respect to the debt securities; or



•

if applicable, make any change that materially and adversely affects the right to convert any debt security pursuant to its terms.

        Each indenture may be supplemented or amended or any provision of that indenture may be waived without the consent of any holders of debt securities issued under that indenture in certain circumstances, including:

•

to cure any ambiguity, omission, defect or inconsistency;



•

to provide for the assumption of LyondellBasell's, LYB International Finance's, LYB International Finance II's or LYB International Finance III's obligations, as applicable, under the applicable indenture by a successor upon any merger, consolidation or asset transfer permitted under that indenture;



•

to provide for uncertificated debt securities in addition to or in place of certificated debt securities;



•

to provide any security for, or to add any guarantees of or obligors on, any series of debt securities or the related guarantees;



•

to conform to this description of debt securities or the description of the notes included in the prospectus supplement with respect to the debt securities of a particular series of debt securities;



•

to comply with any requirement to effect or maintain the qualification of an indenture under the Trust Indenture Act of 1939;

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•

to add covenants that would benefit the holders of any debt securities or to surrender any rights we have under an indenture;



•

to add events of default with respect to any series of debt securities;



•

to make any change that does not adversely affect any outstanding debt securities of any series issued under an indenture in any material respect;



•

to amend or supplement an indenture to permit or facilitate the defeasance and discharge of any series of debt securities pursuant to the applicable provisions of such indenture; and



•

to establish the form or terms of any debt securities and to accept the appointment of a successor trustee, each as permitted under the applicable indenture.

        The holders of a majority in principal amount of the outstanding debt securities of any series (or, in some cases, of all debt securities issued under the indenture that are affected, voting as one class) may waive any existing or past default or event of default with respect to those debt securities. Those holders may not, however, waive any

•

default or event of default in any payment on any debt securities; or



•

compliance with a provision that cannot be amended or supplemented without the consent of each holder affected.

        We, the trustee or the holders of at least 33¹/3% in principal amount of the outstanding debt securities of the applicable series, may at any time call a meeting of the holders of debt securities of a particular series for the following purposes:

•

to give any notice to us or the trustee, or to give any directions to the trustee, or waive any default or event of default and its consequences or to take any other action authorized to be taken by the holders pursuant to the applicable indenture;



•

to remove the trustee and nominate a successor trustee;



•

to consent to the execution of an indenture or of indentures supplemental to an indenture; or



•

to take any other action authorized to be taken by or on behalf of the holders of any specified aggregate principal amount of the debt securities of any one or more or all series, as the case may be, under any other provision of the applicable indenture or under applicable law.

        Any resolution passed or decision taken at any meeting of holders of debt securities of a particular series duly held in accordance with the applicable indenture will be binding on all holders of debt securities of that series. The quorum at any meeting called for the holders of debt securities of a particular series to adopt a resolution will be the presence of persons holding or representing such debt securities of that series in an aggregate principal amount sufficient to take action upon the business for the transaction of which the meeting was called.

        Defeasance.    When we use the term defeasance, we mean discharge from some or all of our obligations under the applicable indenture. If we deposit with the trustee under the indenture any combination of funds or government securities sufficient to make payments on the debt securities of a series issued under that indenture on the dates those payments are due and payable, then, at the option of LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, either of the following will occur:

•

LyondellBasell and, with respect to the LYB International Finance, LYB International Finance II and LYB International Finance III indentures, LyondellBasell and LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, will be discharged from its or their obligations with respect to the debt securities of that series ("legal defeasance"); or

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•

LyondellBasell and, with respect to the LYB International Finance, LYB International Finance II and LYB International Finance III indentures, LyondellBasell and LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, will no longer have any obligation to comply with the restrictive covenants applicable to that series of debt securities, and the related events of default will no longer apply ("covenant defeasance").

        If a series of debt securities is defeased, the holders of the debt securities of the series affected will not be entitled to the benefits of the applicable indenture, except for obligations to register the transfer or exchange of debt securities, replace stolen, lost or mutilated debt securities, maintain paying agencies and hold moneys for payment in trust. In the case of covenant defeasance, the obligation of LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III to pay principal, premium, interest and any additional amounts on the debt securities will also survive.

        Unless we inform you otherwise in the prospectus supplement, we will be required to deliver to the trustee an opinion of counsel that the deposit and related defeasance would not cause the beneficial owners of the debt securities to recognize income, gain or loss for U.S. federal income tax purposes. If we elect legal defeasance, that opinion of counsel must be based upon a ruling from the U.S. Internal Revenue Service or a change in law to that effect.

        Satisfaction and Discharge.    In addition, an indenture will cease to be of further effect with respect to the debt securities of a series issued under that indenture, subject to exceptions relating to compensation and indemnity of the trustee and repayment to us of excess money or government securities, when:

•

either



•

all outstanding debt securities of that series have been delivered to the trustee for cancellation; or



•

all outstanding debt securities of that series not delivered to the trustee for cancellation either:



•

have become due and payable,



•

will become due and payable at their stated maturity within one year, or



•

are to be called for redemption within one year; and



•

any combination of money or government securities in trust sufficient to pay the entire indebtedness on the debt securities of that series when due has been deposited with the trustee; and



•

all other sums payable by LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III with respect to the debt securities of that series have been paid.

        Governing Law.    New York law will govern the indentures, the debt securities and the guarantees.

        Trustee.    Wells Fargo Bank, N.A. is the trustee under the LyondellBasell and LYB International Finance Indenture and will be the trustee under the LYB International Finance III Indenture. Wells Fargo Bank, N.A. serves as trustee or custodian relating to a number of series of debt obligations of LyondellBasell. Certain of Wells Fargo Bank, N.A.'s affiliates perform certain commercial banking services for us for which they receive customary fees. Deutsche Bank Trust Company Americas is the trustee under the LYB International Finance II Indenture. Certain of Deutsche Bank Trust Company Americas' affiliates perform certain commercial banking services for us for which they receive customary fees.

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        Each indenture contains limitations on the right of the trustee, if it or any of its affiliates becomes our creditor, to obtain payment of claims or to realize on certain property received for any such claim, as security or otherwise. The trustee and its affiliates are permitted to engage in other transactions with us. If, however, the trustee acquires any conflicting interest within the meaning of the Trust Indenture Act of 1939, it must eliminate that conflict or resign.

        Form, Exchange, Registration and Transfer.    The debt securities will be issued in registered form, without interest coupons. There will be no service charge for any registration of transfer or exchange of the debt securities. However, payment of any transfer tax or similar governmental charge payable for that registration may be required.

        Debt securities of any series will be exchangeable for other debt securities of the same series, the same total principal amount and the same terms but in different authorized denominations in accordance with the applicable indenture. Holders may present debt securities for registration of transfer at the office of the security registrar or any transfer agent we designate. The security registrar or transfer agent will affect the transfer or exchange if its requirements and the requirements of the applicable indenture are met.

        The trustee will be appointed as security registrar for the debt securities. If a prospectus supplement refers to any transfer agents LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, initially designates, LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, may at any time rescind that designation or approve a change in the location through which any transfer agent acts. We are required to maintain an office or agency for transfers and exchanges in each place of payment. LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, may at any time designate additional transfer agents for any series of debt securities.

        In the case of any redemption, LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, will not be required to register the transfer or exchange of:

•

any debt security during a period beginning 15 business days prior to the mailing of the relevant notice of redemption or repurchase and ending on the close of business on the day of mailing of such notice; or



•

any debt security that has been called for redemption in whole or in part, except the unredeemed portion of any debt security being redeemed in part.

        Payment and Paying Agents.    Unless we inform you otherwise in a prospectus supplement, payments on the debt securities will be made in U.S. dollars at the office of the trustee and any paying agent. At LyondellBasell's, LYB International Finance's, LYB International Finance II's or LYB International Finance III's option, as applicable, however, payments may be made by wire transfer for global debt securities or by check mailed to the address of the person entitled to the payment as it appears in the security register. Unless we inform you otherwise in a prospectus supplement, interest payments may be made to the person in whose name the debt security is registered at the close of business on the record date for the interest payment.

        Unless we inform you otherwise in a prospectus supplement, the trustee under the applicable indenture will be designated as the paying agent for payments on debt securities issued under that indenture. LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts.

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        If the principal of or any premium or interest on debt securities of a series is payable on a day that is not a business day, the payment will be made on the following business day. For these purposes, unless we inform you otherwise in a prospectus supplement, a "business day" is, when used with respect to any place of payment or any other particular location referred to in the indenture or in the debt securities of any series, any day except a Saturday, Sunday or any other day on which commercial banks in such place of payment or other location are authorized or obligated by law or executive order to close.

        Subject to the requirements of any applicable abandoned property laws, the trustee and paying agent will pay to LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, upon written request any money held by them for payments on the debt securities that remains unclaimed for two years after the date upon which that payment has become due. After payment to LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, holders entitled to the money must look to LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as the case may be, for payment. In that case, all liability of the trustee or paying agent with respect to that money will cease.

        Book-Entry Debt Securities.    The debt securities of a series may be issued in the form of one or more global debt securities that would be deposited with a depositary or its nominee identified in the prospectus supplement. Global debt securities may be issued in either temporary or permanent form. We will describe in the prospectus supplement the terms of any depositary arrangement and the rights and limitations of owners of beneficial interests in any global debt security.

        Ranking.    The debt securities will constitute senior debt of LyondellBasell, LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, and will rank equally with all of the other series of debt securities issued under the applicable indenture and will rank senior to all series of subordinated securities issued by them and outstanding from time to time.

        Restrictive Covenants.    Each of the indentures contains restrictions on the activities of LyondellBasell and its subsidiaries for the benefit of holders of the debt securities. The restrictive covenants summarized below will apply to a series of debt securities (unless waived or amended) as long as any of those debt securities are outstanding, unless the prospectus supplement for the series states otherwise. We have used in this summary description of the restrictive covenants the capitalized terms that we have defined below under "Glossary."

Limitation on Liens

        Each indenture provides that LyondellBasell will not, nor will it permit any subsidiary to, create, incur, issue, assume or guarantee any Debt secured by a Lien of or upon any Principal Property or Capital Stock of any subsidiary that directly owns any Principal Property, whether such Principal Property or Capital Stock is owned as of the date of issuance of the applicable debt securities or thereafter acquired, without in any such case making or causing to be made effective provision (and LyondellBasell covenants that in any such case it shall make or cause to be made effective provision) whereby the debt securities (together with, if LyondellBasell shall so determine, any other Debt created, incurred, issued, assumed or guaranteed by LyondellBasell or any subsidiary then existing or thereafter created) shall be secured by such Lien equally and ratably with (or, at the option of LyondellBasell, prior to) such Debt, so long as such Debt shall be so secured. The foregoing restrictions will not, however, apply to Debt secured by Permitted Liens.

        In addition, LyondellBasell or any subsidiary may, without equally and ratably securing the debt securities, issue, assume or guarantee Debt that would otherwise be subject to the foregoing restrictions, if at the time of such issuance, assumption or guarantee, after giving effect thereto and to

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the retirement of any Debt which is concurrently being retired, the aggregate amount of all such Debt secured by Liens which would otherwise be subject to such restriction (other than any Debt secured by Liens permitted as described under clauses (1) through (7) of the definition of Permitted Liens) plus the aggregate amount of all Attributable Debt of LyondellBasell and any of its subsidiaries in respect of Sale and Lease-Back Transactions (with the exception of such transactions which are permitted pursuant to clauses (1) and (2) of the first sentence of the first paragraph under "—Limitation on Sale / Lease-Back Transactions", below does not exceed 15% of Consolidated Net Tangible Assets of LyondellBasell.

Limitation on Sale / Lease-Back Transactions

        LyondellBasell will not, and will not permit any of its subsidiaries to, enter into any Sale and Lease-Back Transaction with respect to any Principal Property unless,

        (1)   LyondellBasell or such subsidiary would (at the time of entering into such arrangement) be entitled pursuant to clause (1) or (6) of the definition of Permitted Liens, without equally and ratably securing the debt securities, to create, issue, assume or guarantee Debt secured by a Lien on such Principal Property; or

        (2)   LyondellBasell or such subsidiary shall apply, within 180 days of the effective date of any such arrangement, an amount not less than the greater of (x) the net proceeds of the sale of such Principal Property or (y) the fair market value (as determined by the Board of Directors of LyondellBasell) of such Principal Property to either the prepayment or retirement (other than any mandatory prepayment or retirement) of Debt incurred or assumed by LyondellBasell or any subsidiary (other than indebtedness owned by LyondellBasell or any subsidiary) which by its terms matures at or is extendible or renewable at the option of the obligor to a date more than twelve months after the date of the creation of such Debt, or to the acquisition, construction or improvement of a manufacturing plant or manufacturing facility; or

        (3)   the Attributable Debt of LyondellBasell and its subsidiary in respect of such Sale and Lease-Back Transaction and all other Sale and Lease-Back Transactions entered into after the Issue Date (other than any such Sale and Lease-Back Transaction as would be permitted as described in clauses (1) and (2) of this covenant, plus the aggregate principal amount of Debt secured by Liens then outstanding (not including any such Debt secured by Liens described in clauses (1) through (7) of the definition of Permitted Liens) which do not equally and ratably secure the debt securities (or secure debt securities on a basis that is prior to other Debt secured thereby) would not exceed 15% of Consolidated Net Tangible Assets of LyondellBasell.

Glossary

        "Attributable Debt" in respect of a Sale and Lease-Back Transaction means, as of any particular time, the present value (discounted at the rate of interest implicit in the terms of the lease involved in such Sale and Lease-Back Transaction, as determined in good faith by LyondellBasell) of the obligation of the lessee thereunder for rental payments (excluding, however, any amounts required to be paid by such lessee, whether or not designated as rent or additional rent, on account of maintenance and repairs, insurance, taxes, assessments, water rates or similar charges or any amounts required to be paid by such lessee thereunder contingent upon the amount of sales, maintenance and repairs, insurance, taxes, assessments, water rates or similar charges) during the remaining term of such lease (including any period for which such lease has been extended or may, at the option of the lessor, be extended).

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        "Capital Stock" means:

        (1)   in the case of a corporation, capital stock or shares;

        (2)   in the case of an association or business entity, any and all shares, interests, participations, rights or other equivalents (however designated) of capital stock;

        (3)   in the case of a partnership or limited liability company, partnership or membership interests (whether general or limited); and

        (4)   any other interest or participation that confers on a person the right to receive a share of the profits and losses of, or distributions of assets of, the issuing person.

        "Consolidated EBITDA" means, for any period, the consolidated operating income plus consolidated depreciation, amortization and other non-cash charges and losses and minus consolidated non-cash credits, gains and income, in each case of LyondellBasell and its subsidiaries for such period; it being understood that such amounts may be determined on a combined basis for a disposed group.

        "Consolidated Net Tangible Assets" means the Total Assets of LyondellBasell and its subsidiaries less goodwill and intangibles (other than intangibles arising from, or relating to, intellectual property, licenses or permits (including, but not limited to, emissions rights) of LyondellBasell and its subsidiaries), in each case calculated in accordance with GAAP, provided, that in the event that LyondellBasell or any of its subsidiaries assumes or acquires any assets in connection with the acquisition by LyondellBasell and its subsidiaries of another person subsequent to the commencement of the period for which the Consolidated Net Tangible Assets is being calculated but prior to the event for which the calculation of the Consolidated Net Tangible Assets is made, then the Consolidated Net Tangible Assets shall be calculated giving pro forma effect to such assumption or acquisition of assets, as if the same had occurred at the beginning of the applicable period.

        "Debt" means any indebtedness for borrowed money.

        "GAAP" means generally accepted accounting principles in the United States set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other entity as may be approved by a significant segment of the accounting profession of the United States, as in effect from time to time. At any time after the Issue Date with respect to a series of debt securities, LyondellBasell may irrevocably elect to apply International Financial Reporting Standards ("IFRS") as issued by the International Accounting Standards Board in lieu of GAAP and, upon any such election, references in the indentures to GAAP shall thereafter be construed to mean IFRS as in effect from time to time. LyondellBasell shall give notice of any such election to the trustee.

        "Issue Date" means, with respect to debt securities of a series, the first date on which the debt securities of such series are originally issued under the applicable indenture.

        "Lien" means any mortgage, security interest, pledge or lien.

        "Permitted Liens" means:

        (1)   Liens of or upon any property acquired, leased, constructed or improved by, or of or upon any shares of Capital Stock or Debt acquired by, LyondellBasell or any subsidiary (i) to secure the payment of all or any part of the purchase price of such property, shares of Capital Stock or Debt upon the acquisition thereof by LyondellBasell or any subsidiary, or (ii) to secure any Debt issued, assumed or guaranteed by LyondellBasell or any subsidiary prior to, at the time of, or within one year after (A) in the case of property, the later of the acquisition, lease, completion of construction (including any improvements on existing property) or commencement of commercial operation of such property or (B) in the case of shares of Capital Stock or Debt,

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the acquisition of such shares of Capital Stock or Debt, which Debt is issued, assumed or guaranteed for the purpose of financing or refinancing all or any part of the purchase price of such property, shares of Capital Stock or Debt and, in the case of property, the cost of construction thereof or improvements thereon;

        (2)   Liens of or upon any property, shares of Capital Stock or Debt existing at the time of acquisition thereof by LyondellBasell or any subsidiary;

        (3)   Liens of or upon any property of a corporation existing at the time such corporation is merged with or into or consolidated with LyondellBasell or any subsidiary or existing at the time of a sale or transfer of the properties of a corporation as an entirety or substantially as an entirety to LyondellBasell or any subsidiary;

        (4)   Liens of or upon (A) any property of, or shares of Capital Stock or Debt of, a person existing at the time such person becomes a subsidiary or (B) any shares of Capital Stock or Debt of a joint venture;

        (5)   Liens to secure Debt of any subsidiary to LyondellBasell or to another subsidiary;

        (6)   Liens in favor of the United States of America or any State thereof, or any department, agency or instrumentality or political subdivision of the United States of America or any State thereof, or in favor of any other country or political subdivision, to secure partial, progress, advance or other payments pursuant to any contract or statute or to secure any Debt incurred or guaranteed for the purpose of financing or refinancing all or any part of the purchase price of the property, shares of Capital Stock or Debt subject to such Liens, or the cost of constructing or improving the property subject to such Liens (including, without limitation, Liens incurred in connection with pollution control, industrial revenue or similar financings); and

        (7)   any extension, renewal or replacement (or successive extensions, renewals or replacements) in whole or in part of any Lien existing on the Issue Date or any Lien referred to in the foregoing clauses (1) through (6), inclusive; provided, however, that the principal amount of Debt secured thereby shall not exceed the principal amount of Debt so secured at the time of such extension, renewal or replacement, and that such extension, renewal or replacement shall be limited to all or a part of the property (plus improvements and construction on such property), shares of Capital Stock or Debt which was subject to the Lien so extended, renewed or replaced.

        "Principal Property" means any single refinery, any single manufacturing plant or any single parcel of real estate, in each case owned by LyondellBasell or any of its subsidiaries, the net book value of which on the date as of which the determination is being made exceeds 1% of Consolidated Net Tangible Assets, other than any such refinery, manufacturing plant or parcel of real estate that, in the opinion of the Board of Directors of LyondellBasell, is not of material importance to the business conducted by LyondellBasell and its subsidiaries as a whole.

        "Sale and Lease-Back Transaction" means the leasing by LyondellBasell or any subsidiary of any Principal Property, whether owned on the Issue Date or acquired after such date (except for temporary leases for a term, including any renewal term, of up to three years and except for leases between LyondellBasell and any subsidiary or between subsidiaries), which Principal Property has been or is to be sold or transferred by LyondellBasell or such subsidiary to any party with the intention of taking back a lease of such Principal Property.

        "Total Assets" means the total consolidated assets of LyondellBasell and its subsidiaries, without giving effect to any amortization of the amount of intangible assets since the Issue Date as shown on the most recent quarterly balance sheet of LyondellBasell, determined on a consolidated basis according to GAAP.

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DESCRIPTION OF GUARANTEES

Guarantee of LYB International Finance, LYB International Finance II and LYB International Finance III Debt Securities

        LyondellBasell will fully and unconditionally guarantee on a senior unsecured basis the full and prompt payment of the principal of, any premium and interest on, and any additional amounts which may be payable by LYB International Finance, LYB International Finance II and LYB International Finance III in respect of the debt securities issued by LYB International Finance, LYB International Finance II and LYB International Finance III, as applicable, when and as the payment becomes due and payable, whether at maturity or otherwise. The guarantees provide that in the event of a default in the payment of principal of, any premium and interest on, and any additional amounts which may be payable by LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable, in respect of such debt securities, the holder of the debt securities may institute legal proceedings directly against LyondellBasell to enforce the guarantees without first proceeding against LYB International Finance, LYB International Finance II or LYB International Finance III, as applicable. The guarantees will rank equally with all of LyondellBasell's other unsecured and unsubordinated debt from time to time outstanding.

Guarantee of LyondellBasell Debt Securities

        LYB International Finance, LYB International Finance II and LYB International Finance III may fully and unconditionally guarantee LyondellBasell's payment obligations under any series of debt securities issued by LyondellBasell. If a series of debt securities is so guaranteed, LYB International Finance, LYB International Finance II and LYB International Finance III, as applicable, will execute a separate guarantee agreement or a supplemental indenture as evidence of its guarantee. We will provide the specific terms of any such guarantee in the applicable prospectus supplement.

DESCRIPTION OF OTHER SECURITIES

        We will set forth in the applicable prospectus supplement a description of any warrants or units that may be offered pursuant to this prospectus.