LYB LyondellBasell Industries NV

DESCRIPTION OF THE NOTES

        The notes will be issued under and pursuant to an indenture to be dated as of October 10, 2019 among LYB International Finance III, as issuer, LyondellBasell, as guarantor, and Wells Fargo Bank, National Association, as trustee. The notes will be issued pursuant to a resolution of LYB International Finance III's sole member, and an accompanying officer's certificate setting forth the specific terms applicable to the 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 guarantee and the indenture and your rights as a holder of the notes.

        The Notes.    The 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 $1,000,000,000;



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mature on October 15, 2049;



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



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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 $2,000 and integral multiples of $1,000 in excess thereof; and



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be issued only in book-entry form represented by global notes registered initially in the name of Cede & Co., as nominee of The Depository Trust Company ("DTC"), or such other name as may be requested by an authorized representative of DTC, and deposited with the trustee, as custodian for DTC.

        Interest on the notes.    Interest on the notes will:

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accrue at the rate of 4.200% per annum;



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accrue from October 10, 2019 or the most recent interest payment date;



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be payable in cash semi-annually on April 15 and October 15 of each year, beginning on April 15, 2020;



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be payable to holders of record on the April 1 and October 1 immediately preceding the related interest payment date; and



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be computed on the basis of a 360-day year consisting of twelve 30-day months.

Payment and Transfer

        Beneficial interests in notes in global form will be shown on, and transfers of interests in notes in global form will be made only through, records maintained by DTC and its direct and indirect participants. Notes in definitive form, if any, may be registered, exchanged or transferred at the office or agency maintained by LYB International Finance III for such purpose (which initially will be the corporate trust office of the trustee).

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        Payment of principal of, premium, if any, and interest on notes in global form registered in the name of or held by DTC or its nominee will be made in immediately available funds to DTC or its nominee, as the case may be, as the registered holder of such global note. If any of the notes are no longer represented by global notes, payment of interest on the notes in definitive form may, at LYB International Finance III's option, be made at the corporate trust office of the trustee.

        No service charge will be made for any registration of transfer or exchange of notes, but LYB International Finance III may require payment of a sum sufficient to cover any transfer tax or other governmental charge payable in connection therewith. LYB International Finance III is not required to transfer or exchange any note selected for redemption for a period beginning 15 business days before the mailing of a notice of redemption of notes to be redeemed and ending on the day of mailing of the notice of redemption.

        The registered holder of a note will be treated as the owner of it for all purposes.

Ranking

        The notes and the guarantee will constitute senior unsecured obligations of LYB International Finance III and LyondellBasell, respectively, and will rank equally in right of payment with all other existing and future senior unsecured indebtedness of LYB International Finance III and LyondellBasell, respectively, and will rank senior in right of payment to any future subordinated indebtedness that LYB International Finance III or LyondellBasell incurs, respectively. The notes and the guarantee will be effectively subordinated to any future secured indebtedness of LYB International Finance III 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 subsidiaries of LYB International Finance III and LyondellBasell (other than LYB International Finance III).

        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 Tender Offer and indebtedness incurred to fund the Tender Offer, the Euro Notes Offering and the use of proceeds therefrom, and 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. LYB International Finance III does not have any currently outstanding indebtedness. 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.

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Optional Redemption

        Prior to the Par Call Date, the notes will be redeemable and repayable, at LYB International Finance III'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 to be redeemed; and



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the sum of the present values of the remaining scheduled payments of principal and interest on the notes to be redeemed that would be due if such notes matured on the Par Call Date (exclusive of interest accrued to the date of redemption) discounted to the date of redemption on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the applicable Treasury Yield plus 35 basis points;

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

        On or after the Par Call Date the notes will be redeemable and repayable, at LYB International Finance III'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 10 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 will state, among other things, the amount of notes 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 III 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 $2,000 or any integral multiple of $1,000 in excess thereof. If less than all the notes are redeemed at any time, the trustee will select the notes to be redeemed on a pro rata basis or by any other method in accordance with the procedures of the Depositary.

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

        "Comparable Treasury Issue" means the United States Treasury security selected by an Independent Investment Banker as having a maturity comparable to the remaining term of the notes, calculated as if the maturity date of the notes were the Par Call Date (the "Remaining Life"), that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the Remaining Life of the notes.

        "Comparable Treasury Price" means, with respect to any redemption date, (i) the average of the Reference Treasury Dealer Quotations obtained by us for the redemption date, after excluding the highest and lowest of all Reference Treasury Dealer Quotations obtained, or (ii) if we obtain fewer than four such Reference Treasury Dealer Quotations, the average of all Reference Treasury Dealer Quotations obtained by us.

        "Independent Investment Banker" means Mizuho Securities USA LLC or Wells Fargo Securities, LLC (and their respective successors), or, if each of such firms is unwilling or unable to select the applicable Comparable Treasury Issue, an independent investment banking institution of national standing appointed by the trustee and reasonably acceptable to LYB International Finance III.

        "Par Call Date" means April 15, 2049 (six months prior to the maturity date).

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        "Reference Treasury Dealer" means each of (i) Mizuho Securities USA LLC and Wells Fargo Securities, LLC, unless either of them ceases to be a primary U.S. government securities dealer in New York City (a "Primary Treasury Dealer"), in which case LYB International Finance III will substitute therefor another Primary Treasury Dealer; and (ii) any two or more other Primary Treasury Dealers selected by LYB International Finance III.

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

        "Treasury Yield" means, with respect to any redemption date applicable to the notes, the rate per annum equal to the semi-annual equivalent yield to maturity (computed as of the third business day immediately preceding the redemption date) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the applicable Comparable Treasury Price for the redemption date.

        Except as set forth above and below under "—Redemption for Changes in Taxes," the notes will not be redeemable by LYB International Finance III 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.

Change of Control Offer

        If a change of control triggering event occurs, unless LYB International Finance III has exercised its option to redeem the notes as described above, each holder of outstanding notes will have the right to require LYB International Finance III to make an offer (a "change of control offer") to repurchase all or any portion (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that holder's notes on the terms set forth in such notes. In a change of control offer, LYB International Finance III 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 or, at LYB International Finance III'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 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 III 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 III will not be required to make a change of control offer upon the occurrence of a change of control triggering event if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by LYB International Finance III and the third party repurchases all notes properly tendered and not withdrawn under its offer. In addition, LYB International Finance III will not repurchase any notes if there has occurred and is continuing on the change of control payment date an event of default under the indenture, other than a default in the payment of the change of control payment upon a change of control triggering event.

        LYB International Finance III 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 as a result of a change of control triggering event. To the extent that the provisions of any securities laws or regulations conflict with the change of control offer provisions of the notes, LYB International Finance III 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 by virtue of any such conflict.

        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

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"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 III offer to repurchase the notes 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, LYB International Finance II's, or LYB International Finance III'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 III to repurchase the notes could cause a default under LyondellBasell's or LYB International Finance III'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 III. Finally, LYB International Finance III's ability to repurchase the notes upon a change of control triggering event 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 III 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 III's obligation to make an offer to repurchase the notes as a result of a change of control triggering event may be waived or modified with the consent of the holders of a majority in aggregate principal amount of the notes.

        "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 or fails to make a rating of the notes 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 is lowered by both of the two rating agencies and the notes 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 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.

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        "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 III'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.

Redemption for Changes in Taxes

        LYB International Finance III may redeem the notes, 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 III 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 guarantee of the notes, LyondellBasell is or would be required to pay additional amounts (as described below under "—Additional Amounts"), 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 LyondellBasell, the change or amendment must become effective after the date that such successor entity first makes payment on the guarantee; 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 LyondellBasell, the change or amendment must become effective after the date that such successor entity first makes payment on the guarantee.

        LYB International Finance III will not give any such notice of redemption earlier than 90 days prior to the earliest date on which LyondellBasell 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

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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 III 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 III to redeem the notes under the indenture. In addition, before LYB International Finance III publishes or mails notice of redemption of the notes as described above, it will deliver to the trustee an officer's certificate to the effect that 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.

        "Tax Jurisdiction" means any jurisdiction in which LyondellBasell (or a successor as 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 is made or deemed to be made by LyondellBasell.

Additional Amounts

        All payments made under or with respect to the guarantee 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 guarantee, including, without limitation, payments of principal, redemption price, purchase price, interest or premium, LyondellBasell will pay such additional amounts as may be necessary in order that the aggregate net amounts received in respect of such payments by the beneficial owners of the notes in respect of the guarantee (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;

        (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 guarantee and/or the exercise or enforcement of rights under the guarantee);

        (3)   any taxes that are imposed or withheld as a result of the failure of the holder of the notes or beneficial owner of the notes 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 III 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);

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        (5)   any payment of principal or interest on the notes 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;

        (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 or with respect to the guarantee;

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

        (9)   any combination of items (1) through (8) above.

        If LyondellBasell becomes aware that it will be obligated to pay additional amounts pursuant to this covenant with respect to any payment with respect to its guarantee of the notes, LyondellBasell 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 LyondellBasell shall notify the trustee promptly thereafter) an officer's certificate of LyondellBasell 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 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. LyondellBasell will provide the trustee with documentation reasonably satisfactory to the trustee evidencing the payment of additional amounts.

        LyondellBasell 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 guarantee. Upon request, LyondellBasell 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 LyondellBasell is incorporated or resident for tax purposes or any jurisdiction from or through which such person makes any payment in respect of the guarantee of such notes and any department or political subdivision thereof or therein.

Future Issuances of Notes

        LYB International Finance III may from time to time, without notice or the consent of the registered holders of the notes, create and issue additional notes ranking identical to the notes 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 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 notes offered hereby for U.S. federal income tax purposes, such additional notes will not have the same "CUSIP" number as the notes offered hereby. There will be no restrictions in the indenture

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or the notes on the amount of additional notes that LYB International Finance III might issue in the future. We may at any time purchase notes in the open market or otherwise at any price.

Book-Entry Systems

        LYB International Finance III will issue the notes in the form of one or more fully registered global notes, without coupons, each of which we refer to as a "global note." Each such global note will be registered in the name of a nominee of The Depository Trust Company, or DTC. Unless and until definitive notes are issued, all references to actions by holders of notes issued in global form refer to actions taken by DTC upon instructions from its participants, and all references to payments and notices to the holders refer to payments and notices to the nominee of DTC as the registered holder of such notes.

        Where appropriate, links will be established among DTC, Euroclear Bank SA/NV, or the Euroclear Operator, as an operator of the Euroclear System, or Euroclear, and Clearstream Banking, S.A., or Clearstream, to facilitate the initial issuance of any notes sold outside of the United States and cross-market transfers of the notes associated with secondary market trading.

        Although DTC, Euroclear and Clearstream have agreed to the procedures described below in order to facilitate transfers of global notes among participants in DTC, Euroclear and Clearstream, they are under no obligation to perform or continue to perform these procedures, and these procedures may be modified or discontinued at any time. None of LYB International Finance III or the trustee or any registrar and transfer agent with respect to the notes will have any responsibility for the performance by DTC, Euroclear, Clearstream or any of their respective direct or indirect participants of their respective obligations under the rules and procedures governing DTC's, Euroclear's or Clearstream's operations.

        While the following information concerning DTC, Euroclear and Clearstream and their respective book-entry systems has been obtained from sources that we believe to be reliable, we do not take any responsibility for the accuracy of that information.

DTC

        DTC has advised us and the underwriters as follows:

        DTC is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code, and a "clearing agency" registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934, as amended.

•

DTC holds securities for its participating organizations, referred to as "direct DTC participants," and facilitates the clearance and settlement of securities transactions, such as transfers and pledges, in deposited securities, through electronic computerized book-entry changes in direct DTC participants' accounts, thereby eliminating the need for physical movement of securities certificates.

        Direct DTC participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. Indirect access to the DTC system is also available to others, referred to as "indirect DTC participants," for example, securities brokers and dealers, banks, trust companies and clearing corporations, that clear through or maintain a custodial relationship with a direct DTC participant, either directly or indirectly.

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•

DTC is owned by The Depository Trust & Clearing Corporation, which is owned by a number of its direct participants and by The New York Stock Exchange, Inc., NYSE American LLC and the Financial Industry Regulatory Authority, Inc.



•

The rules applicable to DTC and its direct and indirect participants are on file with the SEC.

        Purchases of notes under the DTC system must be made by or through direct DTC participants, which will receive a credit for the notes in DTC's records. The ownership interest of each actual purchaser of notes is in turn to be recorded on the direct and indirect DTC participants' records. Beneficial owners of the notes will not receive written confirmation from DTC of their purchase, but beneficial owners are expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the direct or indirect DTC participant through which the beneficial owner entered into the transaction. Transfers of ownership interests in the notes are to be accomplished by entries made on the books of direct and indirect DTC participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the notes, except in the event that use of the book-entry system for the notes is discontinued.

        To facilitate subsequent transfers, all notes deposited by direct DTC participants are registered in the name of DTC's partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of notes with DTC and their registration in the name of Cede & Co. or such other nominee do not affect any change in beneficial ownership. DTC has no knowledge of the actual beneficial owners of the notes; DTC's records reflect only the identity of the direct DTC participants to whose accounts such notes are credited, which may or may not be the beneficial owners. The direct and indirect DTC participants will remain responsible for keeping account of their holdings on behalf of their customers.

        Conveyance of notices and other communications by DTC to direct DTC participants, by direct DTC participants to indirect DTC participants, and by direct DTC participants and indirect DTC participants to beneficial owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time.

        The laws of some jurisdictions may require that certain persons take physical delivery in definitive form of securities which they own. Consequently, those persons may be prohibited from purchasing beneficial interests in the global notes from any beneficial owner or otherwise.

        So long as DTC's nominee is the registered owner of the global notes, such nominee for all purposes will be considered the sole owner or holder of the notes for all purposes under the indenture. Except as provided below, beneficial owners will not be entitled to have any of 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 thereof under the indenture.

        Neither DTC nor Cede & Co. (nor any other DTC nominee) will consent or vote with respect to the notes. Under its usual procedures, DTC mails an omnibus proxy to the issuer as soon as possible after the record date. The omnibus proxy assigns Cede & Co.'s consenting or voting rights to those direct DTC participants to whose accounts the notes are credited on the record date (identified in a listing attached to the omnibus proxy).

        All payments on the global notes will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC. DTC's practice is to credit direct DTC participants' accounts upon DTC's receipt of funds and corresponding detail information from trustees or issuers on payment dates in accordance with their respective holdings shown on DTC's records. Payments by participants to beneficial owners will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers registered in "street name," and will be the responsibility of such participant and not of DTC, the trustee or LYB International Finance III, subject

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to any statutory or regulatory requirements as may be in effect from time to time. Payment of principal and interest to Cede & Co. (or such other nominee as may be requested by an authorized representative of DTC) shall be the responsibility of the trustee or LYB International Finance III, disbursement of such payments to direct DTC participants shall be the responsibility of DTC, and disbursement of such payments to the beneficial owners shall be the responsibility of direct and indirect DTC participants.

        DTC may discontinue providing its service as securities depositary with respect to the notes at any time by giving reasonable notice to us or the trustee. In addition, LYB International Finance III may decide to discontinue use of the system of book-entry transfers through DTC (or a successor securities depositary). Under those circumstances, in the event that a successor securities depositary is not obtained, note certificates in fully registered form are required to be printed and delivered to beneficial owners of the global notes representing such notes.

        None of LYB International Finance III, the trustee and the underwriters will have any responsibility or obligation to direct DTC participants, or the persons for whom they act as nominees, with respect to the accuracy of the records of DTC, its nominee or any direct DTC participant with respect to any ownership interest in the notes, or payments to, or the providing of notice to direct DTC participants or beneficial owners.

        So long as the notes are in DTC's book-entry system, secondary market trading activity in the notes will settle in immediately available funds. LYB International Finance III will make all applicable payments on the notes issued as global notes in immediately available funds.

Euroclear

        Euroclear was created in 1968 to hold securities for participants of Euroclear and to clear and settle transactions between Euroclear participants through simultaneous electronic book-entry delivery against payment, thus eliminating the need for physical movement of certificates and risk from lack of simultaneous transfers of securities and cash. Euroclear provides various other services, including securities lending and borrowing and interfaces with domestic markets in several countries generally similar to the arrangements for cross-market transfers with DTC.

        Euroclear is operated by the Euroclear Operator under a contract with Euroclear Clearance Systems, S.C., a Belgian cooperative, or the "cooperative." The Euroclear Operator conducts all operations, and all Euroclear securities clearance accounts and Euroclear cash accounts are accounts with the Euroclear Operator, not the cooperative. The cooperative establishes policy for Euroclear on behalf of Euroclear participants. Euroclear participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries and may include the underwriters of the securities offered by this prospectus supplement or one or more of their affiliates. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear participant, either directly or indirectly. Euroclear is an indirect DTC participant.

        The Euroclear Operator is a Belgian bank, which is regulated and examined by the Belgian Banking Commission and the National Bank of Belgium.

        The Terms and Conditions Governing Use of Euroclear, the related Operating Procedures of Euroclear and applicable Belgian law govern securities clearance accounts and cash accounts with the Euroclear Operator. Specifically, these terms and conditions govern transfers of securities and cash within Euroclear, withdrawal of securities and cash from Euroclear and receipts of payments with respect to securities in Euroclear.

        All securities in Euroclear are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. The Euroclear Operator acts under the terms and conditions only

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on behalf of Euroclear participants and has no record of or relationship with persons holding securities through Euroclear participants.

        Distributions with respect to the notes held beneficially through Euroclear will be credited to the cash accounts of Euroclear participants in accordance with Euroclear's terms and conditions, to the extent received by the Euroclear Operator and by Euroclear.

        Euroclear will record the ownership interests of its participants in much the same way as does DTC. If DTC is the depositary for the notes, it will record the total ownership of the notes of the U.S. agent of Euroclear as a participant in DTC. When the notes are to be transferred from the account of a direct DTC participant to the account of a Euroclear participant, the purchaser must send instructions to Euroclear through a Euroclear participant at least one day prior to settlement. Euroclear will instruct its U.S. agent to receive the notes against payment. After settlement, Euroclear will credit its participant's account with the interest in the notes purchased. Credit for the notes will appear on the next day (European time).

        In instances in which the notes are held by DTC or its nominee, settlement will take place during New York business hours. Direct DTC participants will be able to employ their usual procedures for sending the notes to the relevant U.S. agent acting for the benefit of Euroclear participants. The sale proceeds will be available to the DTC seller on the settlement date. As a result, to the direct DTC participant, a cross-market transaction will settle no differently than a trade between two direct DTC participants.

        When a Euroclear participant wishes to transfer the notes to a direct DTC participant, the seller will be required to send instructions to Euroclear through a Euroclear participant at least one business day prior to settlement. In these cases, Euroclear will instruct its U.S. agent to transfer these notes against payment for them. The payment will then be reflected in the account of the Euroclear participant the following day, with the proceeds back-valued to the value date, which would be the preceding day, when settlement occurs in New York. If settlement is not completed on the intended value date, that is, the trade fails, proceeds credited to the Euroclear participant's account will instead be valued as of the actual settlement date.

        You should be aware that you will only be able to make and receive deliveries, payments and other communications involving the notes through Euroclear on the days when Euroclear is open for business. Euroclear may not be open for business on days when banks, brokers and other institutions are open for business in the United States. In addition, because of time zone differences, problems may occur when completing transactions involving Euroclear on the same business day as in the United States.

Clearstream

        Clearstream was incorporated as a limited liability company under Luxembourg law. Clearstream is owned by the Deutsche Börse Group. The shareholders of this entity are banks, securities dealers and financial institutions. Clearstream holds securities for its customers and facilitates the clearance and settlement of securities transactions between Clearstream customers through electronic book-entry changes in accounts of Clearstream customers, thus eliminating the need for physical movement of certificates. Clearstream provides to its customers, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities, securities lending and borrowing and collateral management. Clearstream interfaces with domestic markets in a number of countries. Clearstream has established an electronic bridge with the Euroclear Operator to facilitate settlement of trades between Clearstream and Euroclear.

        As a registered bank in Luxembourg, Clearstream is subject to regulation by the Luxembourg Commission for the Supervision of the Financial Sector. Clearstream participants are recognized

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financial institutions around the world, including underwriters, securities brokers and dealers, banks, trust companies and clearing corporations. In the United States, Clearstream participants are limited to securities brokers and dealers and banks, and may include the underwriters of the securities offered by means of this prospectus supplement or one or more of their affiliates. Other institutions that maintain a custodial relationship with a Clearstream participant may obtain indirect access to Clearstream. Clearstream is an indirect DTC participant.

        Distributions with respect to the notes held beneficially through Clearstream will be credited to cash accounts of Clearstream participants in accordance with its rules and procedures, to the extent received by Clearstream.

        Clearstream will record the ownership interests of its participants in much the same way as does DTC. If DTC is the depositary for the notes, it will record the total ownership of the notes of the U.S. agent of Clearstream as a participant in DTC. When the notes are to be transferred from the account of a direct DTC participant to the account of a Clearstream participant, the purchaser must send instructions to Clearstream through a Clearstream participant at least one day prior to settlement. Clearstream will instruct its U.S. agent to receive the notes against payment. After settlement, Clearstream will credit its participant's account with the interest in the notes. Credit for the notes will appear on the next day (European time).

        In instances in which the notes are held by DTC or its nominee, settlement will take place during New York business hours. Direct DTC participants will be able to employ their usual procedures for sending the notes to the relevant U.S. agent acting for the benefit of Clearstream participants. The sale proceeds will be available to the DTC seller on the settlement date. As a result, to the direct DTC participant, a cross-market transaction will settle no differently than a trade between two direct DTC participants.

        When a Clearstream participant wishes to transfer the notes to a direct DTC participant, the seller will be required to send instructions to Clearstream through a Clearstream participant at least one business day prior to settlement. In these cases, Clearstream will instruct its U.S. agent to transfer these notes against payment for them. The payment will then be reflected in the account of the Clearstream participant the following day, with the proceeds back-valued to the value date, which would be the preceding day, when settlement occurs in New York. If settlement is not completed on the intended value date, that is, the trade fails, proceeds credited to the Clearstream participant's account will instead be valued as of the actual settlement date.

        You should be aware that you will only be able to make and receive deliveries, payments and other communications involving the notes through Clearstream on the days when Clearstream is open for business. Clearstream may not be open for business on days when banks, brokers and other institutions are open for business in the United States. In addition, because of time zone differences, problems may occur when completing transactions involving Clearstream on the same business day as in the United States.

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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;



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the title of the debt securities;



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the total principal amount of the debt securities;



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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;



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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;



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



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



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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;



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



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any provisions for optional redemption or early repayment;



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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;



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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;



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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;



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



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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;



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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;



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



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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.