GSK GSK plc

DESCRIPTION OF THE NOTES

The following description of the particular terms of the Notes offered by this prospectus supplement adds, and, to the extent inconsistent therewith, replaces, information in the description of the general terms and provisions of debt securities under the heading “ Description of Debt Securities ” beginning on page 9 of the accompanying prospectus.

General

GSK Capital plc will issue the              Notes, the              Notes, the              Notes and the Floating Rate Notes pursuant to an indenture, dated as of April 6, 2004, among GlaxoSmithKline plc, as guarantor, GSK Capital plc, as issuer, and Deutsche Bank Trust Company Americas, as trustee (as successor to Law Debenture Trust Company of New York, pursuant to an Instrument of Resignation, Appointment and Acceptance dated April 12, 2017, among GSK Capital plc, Law Debenture Trust Company of New York and Deutsche Bank Trust Company Americas), as amended and supplemented by a first supplemental indenture, dated as of March 21, 2014 and as further amended and supplemented by a second supplemental indenture dated as of May 15, 2018 (the “GSK Capital plc Indenture”).

GSK Capital plc will issue the              Notes in the initial aggregate principal amount of $            . The              Notes will mature on             ,              unless redeemed or purchased prior to such date as described below. GSK Capital plc will issue the              Notes in the initial aggregate principal amount of $            . The              Notes will mature on             ,              unless redeemed or purchased prior to such date as described below. GSK Capital plc will issue the              Notes in the initial aggregate principal amount of $            . The              Notes will mature on             ,              unless redeemed or purchased prior to such date as described below. GSK Capital plc will issue the Floating Rate Notes in the initial aggregate principal amount of $            . The Floating Rate Notes will mature on             ,              unless redeemed or purchased prior to such date as described below.

The Notes will be fully and unconditionally guaranteed by GlaxoSmithKline plc. If, for any reason, we do not make any required payment in respect of the Notes when due, whether on the normal due date, on acceleration, redemption or otherwise, GlaxoSmithKline plc will cause the payment to be made to or to the order of the trustee. You will be entitled to payment under the guarantee of GlaxoSmithKline plc without taking any action whatsoever against us.

The issuer will issue the Notes in book-entry form only, in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

As used herein, “business day” means any day other than a Saturday, a Sunday or a day on which banking institutions in the City of New York or London, England are authorized or obligated by law, regulation or executive order to be closed.

We or any of our subsidiaries may at any time and from time to time purchase the Notes of any series in the open market or by tender or by private agreement, if applicable law allows. The Notes of any such series purchased by us or any of our subsidiaries may be held, resold or surrendered by the purchaser thereof through us to the trustee or any paying agent for cancellation.

Interest

Fixed Rate Notes

The Fixed Rate Notes will each bear interest at the applicable interest rate shown on the cover of this prospectus supplement and will accrue interest from                     , 2019, or from the most recent date to which interest has been paid (or provided for), to but not including the next date upon which interest is required to be paid.

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Interest will be payable on each of the              Notes, the              Notes and the              Notes twice a year, on              and             , commencing                     , 2019, to the person in whose name a              Note, a              Note or a              Note, respectively, is registered at the close of business on the              or              that precedes the date on which interest will be paid. Interest on the Notes will be paid on the basis of a 360-day year consisting of twelve 30-day months.

If an interest payment date or redemption date, or the maturity date, for the Fixed Rate Notes, as the case may be, would fall on a day that is not a business day, then the required payment will be made on the next succeeding business day, but no additional interest shall be paid unless we fail to make payment on such next succeeding business day.

Floating Rate Notes

Interest on the Floating Rate Notes will be payable quarterly on             ,             ,              and              of each year, commencing                     , 2019 (each, a “Floating Rate Interest Payment Date”).

The initial interest rate on the Floating Rate Notes for the first Floating Rate Interest Period (as defined below) will be a per annum rate equal to LIBOR, as determined on March    , 2019, plus         % (the “Floating Rate Initial Interest Rate”). Thereafter, the interest rate on the Floating Rate Notes for any Floating Rate Interest Period will be a per annum rate equal to LIBOR, as determined on the applicable Interest Determination Date (as defined below), plus         %.

The interest on the Floating Rate Notes will be reset quarterly every             ,             ,              and              of each year, commencing                     , 2019 (each, an “Interest Reset Date”).

The regular record dates for the Floating Rate Notes will be the 15th calendar day preceding each Floating Rate Interest Payment Date, whether or not a business day. Interest on the Floating Rate Notes will be calculated on the basis of the actual number of days in each Floating Rate Interest Period, assuming a 360-day year.

If a Floating Rate Interest Payment Date, other than the maturity date or a redemption date, for the Floating Rate Notes would fall on a day that is not a business day, the Floating Rate Interest Payment Date will be postponed to the next succeeding business day and interest thereon will continue to accrue to but excluding such succeeding business day, except that if that business day falls in the next succeeding calendar month, the Floating Rate Interest Payment Date will be the immediately preceding business day and interest shall accrue to but excluding such preceding business day. If the maturity date or a redemption date for the Floating Rate Notes would fall on a day that is not a business day, the required payment will be made on the next succeeding business day, but no additional interest shall accrue and be paid unless we fail to make payment on such next succeeding business day.

“Floating Rate Interest Period” means the period beginning on (and including) March    , 2019, in the case of the initial period, or thereafter a Floating Rate Interest Payment Date and ending on (but excluding) the next succeeding Floating Rate Interest Payment Date.

“Interest Determination Date” means March    , 2019, in the case of the initial period, or thereafter, the second London banking day preceding the applicable Interest Reset Date.

“London banking day” means any day on which dealings in U.S. dollars are transacted in the London interbank market.

LIBOR will be determined by the calculation agent in accordance with the following provisions:

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“Reuters Page LIBOR01” means the display that appears on Reuters Page LIBOR01 or any page as may replace such page on such service (or any successor service) for the purpose of displaying LIBOR of major banks for U.S. dollars.

By its acquisition of Floating Rate Notes, each holder of Floating Rate Notes (including each holder of a beneficial interest in Floating Rate Notes) acknowledges, accepts, consents and agrees to be bound by the determination of the Alternative Rate by the central bank, reserve bank, monetary authority, any similar

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institution (including any committee or working group thereof) or the IFA and any Adjustments to the Alternative Rate and the spread thereon that we direct the calculation agent to make, including as may occur without any prior notice from us and without the need for us to obtain any further consent from such holder of Floating Rate Notes.

Covenants

Subject to certain exceptions, if we are required to withhold or deduct any amount for or on account of any U.K. or U.S. withholding tax from any payment made on the Notes, we will pay additional amounts on those payments so that the amount received by noteholders will equal the amount that would have been received if no such taxes had been applicable. See “ Description of the Notes—Covenants—Payment of Additional Amounts. ”

As contemplated by the last paragraph under “ Description of Debt Securities—Defeasance ” beginning on page 19 of the accompanying prospectus, the satisfaction of certain conditions will permit us to omit to comply with some or all of our obligations, covenants and agreements under the GSK Capital plc Indenture with respect to the Notes of any or all series, as applicable. In addition, we may omit to comply with certain covenants through covenant defeasance. We refer you to the information under “ Description of Debt Securities—Defeasance ” in the accompanying prospectus for more information on how we may do this.

Except as described in this prospectus supplement and the accompanying prospectus, the GSK Capital plc Indenture does not contain any covenants or other provisions designed to protect holders of the Notes against a reduction in our creditworthiness in the event of a highly leveraged transaction or that would prohibit other transactions that might adversely affect holders of the Notes, including, among other things, through the incurrence of additional indebtedness.

Payment of Additional Amounts

The provisions of the GSK Capital plc Indenture described under “ Description of Debt Securities — Covenants — Payment of Additional Amounts ” in the accompanying prospectus do not apply to the Notes. The following payment of additional amounts provisions apply to the Notes.

Payments made by us under or with respect to the Notes will be free and clear of and without withholding or deduction for or on account of any present or future tax, duty, levy, impost, assessment or other governmental charge of any nature whatsoever imposed or levied by or on behalf of (i) the government of the United Kingdom or of any territory of the United Kingdom or by any authority or agency therein or thereof having the power to tax or (ii) the government of the United States or any state or territory of the United States or by any authority or agency therein or thereof having the power to tax, which we refer to collectively as “Taxes,” unless we are required to withhold or deduct Taxes by law.

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

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nor shall additional amounts be paid with respect to any payment of the principal of or premium, if any, or interest on any Notes to any such holder who is a fiduciary or a partnership or a beneficial owner who is other than the sole beneficial owner of such payment to the extent a beneficiary or settlor with respect to such fiduciary or a member of such partnership or a beneficial owner would not have been entitled to such additional amounts had it been the holder of such Notes.

We have agreed in the GSK Capital plc Indenture that at least one paying agent for the Notes will be located outside the United Kingdom.

Our obligation to pay additional amounts if and when due will survive the termination of the GSK Capital plc Indenture and the payment of all amounts in respect of the Notes.

Tax Redemption

In the event of changes in U.K. or U.S. withholding taxes applicable to payments of interest, we may redeem the Notes of a series in whole (but not in part) at any time prior to maturity, at a price equal to 100% of their principal amount plus accrued interest to the redemption date. See “ Description of Debt Securities — Optional Redemption for Tax Reasons ” in the accompanying prospectus.

Optional Make-Whole Redemption

Prior to the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to the greater of (i) 100% of the principal amount of

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the              Notes to be redeemed on that redemption date; and (ii) as determined by the quotation agent (as defined below), the sum of the present values of the remaining scheduled payments of principal of and interest on the              Notes to be redeemed on that redemption date (not including any portion of such payments of interest accrued as of the redemption date) that would be due if the              Notes matured on the              Notes Par Call Date, discounted to the redemption date on a semi-annual basis (assuming a 360 day year consisting of twelve 30 day months) at the Treasury Rate plus         %, plus accrued and unpaid interest thereon to, but excluding, the redemption date. On or after the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to 100% of the principal amount of the              Notes to be redeemed, plus accrued and unpaid interest, if any, thereon to, but excluding, the redemption date.

Prior to the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to the greater of (i) 100% of the principal amount of the              Notes to be redeemed on that redemption date; and (ii) as determined by the quotation agent (as defined below), the sum of the present values of the remaining scheduled payments of principal of and interest on the              Notes to be redeemed on that redemption date (not including any portion of such payments of interest accrued as of the redemption date) that would be due if the              Notes matured on the              Notes Par Call Date, discounted to the redemption date on a semi-annual basis (assuming a 360 day year consisting of twelve 30 day months) at the Treasury Rate plus         %, plus accrued and unpaid interest thereon to, but excluding, the redemption date. On or after the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to 100% of the principal amount of the              Notes to be redeemed, plus accrued and unpaid interest, if any, thereon to, but excluding, the redemption date.

Prior to the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to the greater of (i) 100% of the principal amount of the              Notes to be redeemed on that redemption date; and (ii) as determined by the quotation agent (as defined below), the sum of the present values of the remaining scheduled payments of principal of and interest on the              Notes to be redeemed on that redemption date (not including any portion of such payments of interest accrued as of the redemption date) that would be due if the              Notes matured on the              Notes Par Call Date, discounted to the redemption date on a semi-annual basis (assuming a 360 day year consisting of twelve 30 day months) at the Treasury Rate plus         %, plus accrued and unpaid interest thereon to, but excluding, the redemption date. On or after the              Notes Par Call Date, we may redeem the              Notes, in whole or in part, at our option at any time and from time to time at a redemption price equal to 100% of the principal amount of the              Notes to be redeemed, plus accrued and unpaid interest, if any, thereon to, but excluding, the redemption date.

Notwithstanding the foregoing, installments of interest on the Fixed Rate Notes to be redeemed that are due and payable on an interest payment date falling on or prior to a redemption date will be payable on the interest payment date to the registered holders as of the close of business on the relevant record date according to the Fixed Rate Notes and the GSK Capital plc Indenture, as applicable.

“Comparable Treasury Issue” means the United States Treasury security selected by the quotation agent as having a maturity comparable to the remaining term of the Fixed Rate Notes of the applicable series to be redeemed, assuming such Fixed Rate Notes matured on the applicable Par Call Date, that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of such Fixed Rate Notes, assuming such Fixed Rate Notes matured on the applicable Par Call Date.

“Comparable Treasury Price” means, with respect to any redemption date, (i) the average of four Reference Treasury Dealer Quotations (as defined below) for such redemption date, after excluding the highest and lowest such Reference Treasury Dealer Quotations, or (ii) if the quotation agent for the Notes obtains fewer than four such Reference Treasury Dealer Quotations, the average of all such quotations, or (iii) if only one Reference Treasury Dealer Quotation is received, the quotation.

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“Quotation agent” means any Reference Treasury Dealer appointed by us.

“Reference Treasury Dealer” means (i) each of Deutsche Bank Securities Inc., Goldman Sachs & Co. LLC, HSBC Securities (USA) Inc. and Merrill Lynch, Pierce, Fenner & Smith Incorporated (or their respective affiliates that are Primary Treasury Dealers) and their respective successors; provided, however, that if any of the foregoing shall cease to be a primary U.S. government securities dealer in the United States (a “Primary Treasury Dealer”), we will substitute therefor another Primary Treasury Dealer, and (ii) any other Primary Treasury Dealer selected by us.

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

“Treasury Rate” means, with respect to any redemption date, the rate per annum equal to the semi-annual equivalent yield to maturity of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for that redemption date.

Notice of any redemption will be mailed at least 15 days but not more than 60 days before the redemption date to each registered holder of the Fixed Rate Notes of the applicable series to be redeemed by us or by the trustee on our behalf. Notice of redemption will be published in a daily newspaper of general circulation in the United States, and we will give notice of any such redemption to any exchange on which such Notes are listed. On and after any redemption date, interest will cease to accrue on the Fixed Rate Notes or portions thereof called for redemption. On or before the redemption date, we will deposit with a paying agent (or the trustee) money sufficient to pay the redemption price of and accrued interest on the Fixed Rate Notes to be redeemed on that date. If less than all of the Fixed Rate Notes of the applicable series are to be redeemed, the Fixed Rate Notes to be redeemed shall be selected by lot by DTC, in the case of Notes represented by a global security, or by the trustee by such method as the trustee deems to be fair and appropriate, in the case of Notes that are not represented by a global security.

Events of Default

The events of default under the GSK Capital plc Indenture, as applicable, with respect to the Notes are defined under “ Description of Debt Securities—Events of Default ” on page 16 of the accompanying prospectus.

Further Issuances

We are initially offering the              Notes in the aggregate principal amount of $            , the              Notes in the aggregate principal amount of $            , the              Notes in the aggregate principal amount of $             and the Floating Rate Notes in the aggregate principal amount of $            . We may from time to time, without the consent of the holders of a series of Notes, create and issue further debt securities of the same series having the same terms and conditions in all respects as the applicable Notes being offered hereby, except for the issue date, the issue price and the first payment of interest thereon. Any such additional debt securities shall be issued under a separate CUSIP or ISIN number unless the additional debt securities are issued pursuant to a “qualified reopening” of the original series, are otherwise treated as part of the same “issue” of debt instruments as the original series or are issued with no more than a de minimis amount of original discount, in each case for U.S. federal income tax purposes.

Book-Entry System

We will issue the Notes of each series in the form of one or more fully registered global securities. We will deposit these global securities with, or on behalf of, DTC and register these securities in the name of DTC’s

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nominee. Direct and indirect participants in DTC will record beneficial ownership of the Notes by individual investors. The transfer of ownership of beneficial interests in a global security will be effected only through records maintained by DTC or its nominee, or by participants or persons that hold through participants.

Investors may elect to hold beneficial interests in the global securities through either DTC, Clearstream or Euroclear if they are participants in these systems, or indirectly through organizations which are participants in these systems. Beneficial interests in the global securities will be held in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.

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

DTC holds securities of institutions that have accounts with it or its participants. Through its maintenance of an electronic book-entry system, DTC facilitates the clearance and settlement of securities transactions among its participants and eliminates the need to deliver securities certificates physically. DTC’s participants include securities brokers and dealers, including the underwriters of this offering, banks, trust companies, clearing corporations and other organizations. DTC is partially owned by some of these participants or their representatives. Access to DTC’s book-entry system is also available to others such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a participant, either directly or indirectly. DTC agrees with and represents to its participants that it will administer its book-entry system in accordance with its rules and bylaws and requirements of law. The rules applicable to DTC and its participants are on file with the Commission.

Clearstream and Euroclear will hold interests on behalf of their participants through customers’ securities accounts in Clearstream’s and Euroclear’s names on the books of their respective depositaries, which in turn will hold interests in customers’ securities accounts in the depositaries’ names on the books of DTC. At the present time, Citibank, N.A. acts as U.S. depositary for Clearstream and JPMorgan Chase Bank, N.A. acts as U.S. depositary for Euroclear, or, collectively, the “U.S. Depositaries.”

Clearstream holds securities for its participating organizations, or “Clearstream Participants,” and facilitates the clearance and settlement of securities transactions between Clearstream Participants through electronic book-entry changes in accounts of Clearstream Participants, thereby eliminating the need for physical movement of certificates. Clearstream provides to Clearstream Participants, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic markets in several countries.

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

Distributions with respect to the Notes of a series 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 the U.S. Depositary for Clearstream.

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Euroclear holds securities and book-entry interests in securities for participating organizations, or “Euroclear Participants” and facilitates the clearance and settlement of securities transactions between Euroclear Participants, and between Euroclear Participants and participants of certain other securities intermediaries through electronic book-entry changes in accounts of such participants or other securities intermediaries. Euroclear provides Euroclear Participants with, among other things, safekeeping, administration, clearance and settlement, securities lending and borrowing, and related services.

Euroclear Participants are investment banks, securities brokers and dealers, banks, central banks, supranationals, custodians, investment managers, corporations, trust companies and certain other organizations and may include the underwriters or their affiliates. Non-participants in Euroclear may hold and transfer beneficial interests in a global security through accounts with a Euroclear Participant or any other securities intermediary that holds a book-entry interest in a global security through one or more securities intermediaries standing between such other securities intermediary and Euroclear.

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

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

Cross-market transfers between DTC’s participating organizations, or the “DTC Participants,” on the one hand, and Euroclear Participants or Clearstream Participants, on the other hand, will be effected through DTC in accordance with DTC’s rules on behalf of Euroclear or Clearstream, as the case may be, by its U.S. Depositary; however, such cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in such system in accordance with the rules and procedures and within the established deadlines (European time) of such system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its U.S. Depositary to take action to effect final settlement on its behalf by delivering or receiving interests in the global security in DTC, and making or receiving payment in accordance with normal procedures for same-day fund settlement applicable to DTC. Euroclear Participants and Clearstream Participants may not deliver instructions directly to their respective U.S. Depositaries.

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

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

None of us, any of the underwriters and the trustee will have any responsibility for the performance by DTC, Euroclear or Clearstream or their respective participants of their respective obligations under the rules and procedures governing their operations.

Although DTC, Clearstream and Euroclear have agreed to the foregoing procedures in order to facilitate transfers of securities among participants of DTC, Clearstream and Euroclear, they are under no obligation to perform or continue to perform such procedures and they may discontinue the procedures at any time.

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Same-Day Settlement and Payment

Initial settlement for the Notes will be made in immediately available funds. Secondary market trading between DTC participants will occur in the ordinary way in accordance with DTC rules and will be settled in immediately available funds using DTC’s Same-Day Funds Settlement System.

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TAX CONSIDERATIONS

The following discussion summarizes material considerations relating to U.S. federal income tax and U.K. tax, and is based upon laws, regulations, decrees, rulings, administrative practice and judicial decisions in effect at the date of this prospectus supplement. Legislative, judicial or administrative changes or interpretations may, however, be forthcoming. Any such changes or interpretations could affect the tax consequences to holders of the Notes, possibly on a retroactive basis, and could affect the continued validity of the statements and conclusions set forth herein.

This summary does not purport to address all of the tax considerations that may be relevant to a holder of the Notes. Prospective purchasers of the Notes are advised to consult their own tax advisers as to the tax consequences of a purchase of Notes including, without limitation, the consequences of the receipt of interest and (if applicable) any premium on, and of the sale or redemption of, the Notes or any interest therein.

The summary in respect of U.K. tax considerations does not deal with the position of certain classes of noteholders, such as dealers, and relates only to those persons who are the absolute beneficial owners of the Notes and who hold the Notes as an investment.

United States Taxation

The following discussion summarizes material U.S. federal income tax considerations that may be relevant to you if you purchase Notes in the initial offering at the original issue price. This summary is based on provisions of the Internal Revenue Code of 1986, as amended, applicable Treasury regulations, laws, rulings and decisions now in effect, all of which are subject to change, possibly with retroactive effect. This summary deals only with beneficial owners of Notes that will hold Notes as capital assets. It does not address certain considerations that may be relevant to you if you are an investor that is subject to special tax rules, such as a bank, thrift, real estate investment trust, regulated investment company, insurance company, pass-through entity, dealer in securities or currencies, trader in securities or commodities that elects mark-to-market treatment, a person that will hold Notes as a hedge against currency risk or as a position in a “straddle” or conversion transaction, or as part of a “synthetic security” or other integrated financial transaction, U.S. expatriates, tax-exempt organizations or a person whose “functional currency” is not the U.S. dollar.

This summary addresses only U.S. federal income tax consequences, and does not address consequences arising under state, local, foreign tax laws or the Medicare tax on net investment income. You should consult your tax adviser about the tax consequences of holding Notes, including the relevance to your particular situation of the considerations discussed below, as well as the relevance to your particular situation of state, local, non-U.S., or other tax laws.

As used herein, a “U.S. Holder” is an individual who is a citizen or resident of the United States, a U.S. domestic corporation, or any other person that is subject to U.S. federal income tax on a net income basis in respect of an investment in the Notes. A “Non-U.S. Holder” is a beneficial owner of a Note that is an individual, corporation, foreign estate, or foreign trust that is not a U.S. Holder.

U.S. Holders that use an accrual method of accounting for tax purposes (“accrual method holders”) generally are required to include certain amounts in income no later than the time such amounts are reflected on certain financial statements (the “book/tax conformity rule”). The application of the book/tax conformity rule thus may require the accrual of income earlier than would be the case under the general tax rules described below, although it is not clear to what types of income the book/tax conformity rule applies. Accrual method holders should consult with their tax advisors regarding the potential applicability of the book/tax conformity rule to their particular situation.

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U.S. Holders

Payments of Interest

Payments or accruals of interest on a Note will be taxable to you as ordinary interest income at the time that you receive or accrue such amounts (in accordance with your regular method of tax accounting). It is expected, and this discussion assumes, that the Notes will not be issued with more than a de minimis amount of original issue discount (“OID”). In general, however, if the Notes are issued with more than de minimis OID, a U.S. Holder will be required to include OID in gross income, as ordinary income, under a “constant-yield method” before the receipt of cash attributable to such income, regardless of the U.S. Holder’s regular method of accounting for U.S. federal income tax purposes.

Sale or Exchange of Notes

Upon the sale, exchange or other taxable disposition of a Note, you generally will recognize gain or loss equal to the difference between the amount realized on the disposition (less any accrued and unpaid interest, which will be taxable as such) and your adjusted tax basis in such Note (generally, its cost to you less any principal payments previously received). A U.S. Holder also generally will recognize gain or loss, as described further below, if GlaxoSmithKline plc or another subsidiary of GlaxoSmithKline plc (a “GSK entity”) assumes the obligations of GlaxoSmithKline Capital plc, as described under “ Description of Debt Securities — Substitution of Issuer ” in the accompanying prospectus. Any such gain or loss generally will be U.S.-source capital gain or loss and will be long-term capital gain or loss, subject to taxation at reduced rates for individual taxpayers, if you have held the Note for more than one year. The deductibility of capital losses is subject to limitations.

Substitution of a GSK Entity for GlaxoSmithKline Capital plc as Issuer

For U.S. federal income tax purposes, an assumption by a GSK entity of all the rights and obligations of GlaxoSmithKline Capital plc, as described under “ Description of Debt Securities—Substitution of Issuer ” in the accompanying prospectus, generally would be treated as a deemed taxable exchange of Notes for new Notes issued by such GSK entity. You generally will recognize capital gain or loss in an amount equal to the difference between the issue price, as described below, of the new Notes and your adjusted tax basis in the Notes, as described above.

Assuming the new Notes are considered to be “traded on an established market” for U.S. federal income tax purposes, the issue price of the new Notes would be the fair market value of such Notes on their issue date. We expect that any new Notes will be considered to be traded on an established market.

Depending on their issue price, the new Notes may be issued with OID or premium for U.S. federal income tax purposes. Subject to a de minimis exception, the amount of OID, if any, would be equal to the excess of the stated principal amount of the new Notes over the issue price of the new Notes and generally would be includible in income over the term of the new Notes under a constant-yield method. The amount of premium, if any, would be equal to the excess of the issue price of the new Notes over the stated principal amount of the new Notes, and a U.S. Holder could elect to amortize any such premium under a constant-yield method over the term of the new Notes as an offset to interest income on the new Notes. A U.S. Holder that makes such an election would have to reduce its tax basis in a Note by the amount of the premium amortized during its holding period. Any such election generally would apply to all obligations owned or acquired by the U.S. Holder in that taxable year and all subsequent taxable years and could not be revoked without the permission of the U.S. Internal Revenue Service (“IRS”).

The substitution of issuers also may have other U.S. federal income tax consequences. You should consult your own tax adviser in the event that there is a substitution of issuers.

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Non-U.S. Holders

Payments of Interest.

Payments of interest on the Notes to a non-U.S. Holder generally will not be subject to U.S. withholding tax unless GlaxoSmithKline Capital Inc. or another U.S. GSK entity assumes GlaxoSmithKline Capital plc’s obligations under the Notes as described under “Description of Debt Securities—Substitution of Issuer” in the accompanying prospectus. In the event of such a substitution, subject to the discussions below under “— FATCA ” and “ Information Reporting and Backup Withholding ,” payments of interest on the Notes to a Non-U.S. Holder generally will be exempt from withholding of U.S. federal income tax under the portfolio interest exemption provided that (i) the Non-U.S. Holder properly certifies as to its foreign status by providing a properly executed IRS Form W-8BEN or W-8BEN-E (or appropriate substitute form) to the applicable withholding agent; (ii) the Non-U.S. Holder does not actually or constructively own 10% or more of the total combined voting power of our stock entitled to vote; and (iii) the Non-U.S. Holder is not a controlled foreign corporation that is related to us actually or constructively through stock ownership.

Sale, Exchange and Retirement of Notes.

Subject to the discussion below under “ Information Reporting and Backup Withholding ,” a Non-U.S. Holder generally will not be subject to U.S. federal income tax on gain recognized on a sale, exchange or retirement of Notes, provided, in the case of a non-U.S. Holder that is an individual, the non-U.S. Holder is not present in the United States for 183 days or more in the year of the sale and certain other conditions are met.

FATCA

Under the U.S. tax rules known as the Foreign Account Tax Compliance Act (“FATCA”) and the regulations and administrative guidance promulgated thereunder, in the event that GlaxoSmithKline Capital Inc. or another U.S. GSK entity assumes GlaxoSmithKline Capital plc’s obligations under the Notes as described under “Description of Debt Securities—Substitution of Issuer” in the accompanying prospectus, a holder of the Notes will generally be subject to 30% U.S. withholding tax on interest payments on the Notes if the holder is not FATCA compliant, or holds its Notes through a foreign financial institution that is not FATCA compliant. In order to be treated as FATCA compliant, a holder must provide us or an applicable financial institution certain documentation (usually an IRS Form W-8BEN or W-8BEN-E) containing information about its identity, its FATCA status, and if required, its direct and indirect U.S. owners. These requirements may be modified by the adoption or implementation of an intergovernmental agreement between the United States and another country or by future U.S. Treasury Regulations. If any taxes are required to be deducted or withheld from any payments in respect of the Notes as a result of a beneficial owner or intermediary’s failure to comply with the foregoing rules, no additional amounts will be paid on the Notes as a result of the deduction or withholding of such tax.

Documentation that holders provide in order to be treated as FATCA compliant may be reported to the IRS and other tax authorities, including information about a holder’s identity, its FATCA status, and if applicable, its direct and indirect U.S. owners. Prospective investors should consult their own tax advisers about how information reporting and the possible imposition of withholding tax under FATCA may apply to their investment in the Notes.

Information Reporting and Backup Withholding

Information returns will be filed with the IRS in connection with payments on the Notes made to, and the proceeds of dispositions of Notes effected by, certain U.S. Holders. In addition, certain U.S. Holders may be subject to U.S. backup withholding on such amounts if they do not provide their taxpayer identification number to the person from whom they receive payments. Non-U.S. Holders may have to comply with certification procedures to establish that they are not U.S. Holders in order to avoid information reporting and backup withholding requirements. Amounts withheld as backup withholding generally may be credited against a U.S.

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Holder’s U.S. federal income tax liability. A U.S. Holder may obtain a refund of any excess amounts withheld under the backup withholding rules by filing the appropriate claim for refund with the IRS and timely furnishing any required information.

U.K. Taxation

Payments of Interest

Payments of interest on the Notes may be made without withholding or deduction for or on account of U.K. tax under the provisions of U.K. tax law relating to “quoted Eurobonds”, within the meaning of section 987 of the Income Tax Act 2007 (the “Act”), as long as the Notes carry a right to interest and are and continue to be listed on a “recognised stock exchange” within the meaning of section 1005 of the Act. The New York Stock Exchange is a “recognised stock exchange” for these purposes. Accordingly, interest payments made on the Notes will be payable without withholding or deduction for or on account of U.K. tax if, at the time of such payments, the Notes are both admitted to trading and listed on the New York Stock Exchange.

If the Notes are not, or cease to be, listed on a “recognised stock exchange,” interest may, if found to have a U.K. source, be paid after deduction of U.K. income tax at the basic rate, currently, of 20%, although if you are eligible for the benefits of a relevant tax treaty you may be entitled to a reduced rate of withholding. Currently, an Eligible U.S. Investor (as defined in the accompanying prospectus) would be entitled to receive payments of U.K. source interest free of U.K. withholding tax subject to obtaining a direction to that effect from HM Revenue & Customs. However, a direction will only be issued on prior application to HM Revenue & Customs.

To the extent that payments of interest on a Note constitute U.K. source income for U.K. tax purposes they will remain subject to U.K. income tax by direct assessment even where paid without deduction of any U.K. withholding tax. However, where U.K. source interest is paid without deduction of any U.K. withholding tax, the interest will generally not be assessed to U.K. tax in the hands of holders of Notes who (like Eligible U.S. Investors) are not resident in the United Kingdom for tax purposes, except where such persons carry on a trade, profession or vocation in the United Kingdom through a U.K. permanent establishment (or, in the case of individuals, through a branch or agency) to which the holding of the Notes is attributable, in which case (subject to exemptions for interest received by certain categories of agent) tax may be levied on the U.K. permanent establishment (or on the branch or agency).

As indicated under “ Description of the Notes — Covenants — Payment of Additional Amounts ,” holders of Notes should note that the provisions relating to additional amounts would not apply if HM Revenue & Customs sought to assess directly the person entitled to the relevant interest to U.K. tax. However, exemption from, or reduction of, such U.K. tax liability might be available under an applicable tax treaty.

Purchase, Sale and Retirement of Notes

Investors who are not resident in the United Kingdom for tax purposes (including Eligible U.S. Investors) will not be liable for U.K. taxation on capital gains realized on the sale or other disposal or redemption of a Note, except where such persons carry on a trade, profession or vocation in the United Kingdom through a U.K. permanent establishment (or, in the case of individuals, through a branch or agency) to which the holding of Notes is attributable.

U.K. Stamp Taxes in Relation to Notes

No U.K. stamp duty or stamp duty reserve tax is payable on the issue of the Notes and their deposit with, or on behalf, of DTC. No U.K. stamp duty reserve tax will be payable in respect of any subsequent dealings in the Notes where such dealings are effected through DTC’s electronic book-entry system, nor will U.K. stamp duty be payable in respect of such subsequent dealings when they are effected in accordance with the normal electronic book-entry procedures of DTC and not by a written instrument of transfer.

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Payment of Principal

The payment of principal (and premium, if any) on the Notes may be made without withholding or deduction for or on account of U.K. tax.

Payment by GlaxoSmithKline plc as Guarantor

As a matter of U.K. tax law, it is possible that payments made by GlaxoSmithKline plc as guarantor would be subject to withholding on account of U.K. tax. This withholding would be subject to any relief that may be available and claimed under any applicable double tax treaty.

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DESCRIPTION OF DEBT SECURITIES

This section describes the general terms that will apply to any debt securities that we may offer pursuant to this prospectus, other than as noted otherwise in this section. The specific terms of any offered debt securities, and the extent to which the general terms described in this section apply to those debt securities, will be described in the related prospectus supplement at the time of the offer.

General

As used in this prospectus, “debt securities” means the debentures, notes, bonds, guarantees and other evidences of indebtedness that GlaxoSmithKline issues or that a finance subsidiary issues and GlaxoSmithKline fully and unconditionally guarantees and, in each case, the trustee authenticates and delivers under the applicable indenture. The debt securities will be our direct unsecured obligations and will rank equally and ratably without preference among themselves and at least equally with all of our other unsecured and unsubordinated indebtedness.

The debt securities will be issued in one or more series under an indenture dated as of March 4, 2008 between GlaxoSmithKline and Deutsche Bank Trust Company Americas, as trustee (the “trustee”) (as successor to Law Debenture Trust Company of New York, pursuant to an Instrument of Resignation, Appointment and Acceptance dated April 12, 2017 among GlaxoSmithKline, the trustee and Law Debenture Trust Company of New York), as supplemented by a first supplemental indenture dated as of March 21, 2014 between GlaxoSmithKline and the trustee (the “GSK plc Indenture”), an indenture dated as of April 6, 2004 among GlaxoSmithKline Capital plc, GlaxoSmithKline, as guarantor, and the trustee (as successor to Law Debenture Trust Company of New York, pursuant to an Instrument of Resignation, Appointment and Acceptance dated April 12, 2017 among GlaxoSmithKline Capital plc, the guarantor, the trustee and Law Debenture Trust Company of New York), as supplemented by a first supplemental indenture dated as of March 21, 2014 among GlaxoSmithKline Capital plc, the guarantor and the trustee (the “GSK Capital plc Indenture”), or an indenture dated as of April 6, 2004 among GlaxoSmithKline Capital Inc., the guarantor and the trustee (as successor to Law Debenture Trust Company of New York, pursuant to an Instrument of Resignation, Appointment and Acceptance dated April 12, 2017, among GlaxoSmithKline Capital Inc., the guarantor, the trustee and Law Debenture Trust Company of New York), as supplemented by a first supplemental indenture dated as of March 18, 2013 among GlaxoSmithKline Capital Inc., the guarantor and the trustee and a second supplemental indenture dated as of March 21, 2014 among GlaxoSmithKline Capital Inc., the guarantor and the trustee (the “GSK Capital Inc. Indenture”). Each of the GSK plc Indenture, the GSK Capital plc Indenture and the GSK Capital Inc. Indenture has been qualified under the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”). In the following discussion, we sometimes refer to these indentures collectively as the “indentures.”

This prospectus briefly outlines the provisions of the indentures and is qualified in its entirety by reference to the indentures. The terms of the indentures will include both those stated in the indentures and those made part of the indentures by the Trust Indenture Act. The indentures have been filed 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.

The indentures do not contain any covenants or other provisions designed to protect holders of the debt securities against a reduction in the creditworthiness of GlaxoSmithKline or the finance subsidiaries in the event of a highly leveraged transaction or that would prohibit other transactions that might adversely affect holders of the debt securities.

Issuances in Series

The indentures do not limit the amount of debt securities that may be issued. The debt securities may be issued in one or more series with the same or various maturities, at a price of 100% of their principal amount or

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at a premium or a discount. Not all debt securities of any one series need be issued at the same time, and, unless otherwise provided, any series may be reopened, without the consents of the holders of debt securities of that series, for issuances of additional debt securities of that series. Except in the limited circumstances described below under “—Covenants—Limitation on Liens,” the debt securities will not be secured by any property or assets of GlaxoSmithKline, as issuer or guarantor, or the finance subsidiaries.

The terms of any authorized series of debt securities will be described in a prospectus supplement. These terms will include some or all of the following:

Debt securities that have a maturity of less than one year from their date of issue and in respect of which the proceeds are to be received by us in the United Kingdom will have a minimum denomination of £100,000 (or its equivalent in another currency).

The prospectus supplement relating to any series of debt securities may add to or change statements contained in this prospectus. The prospectus supplement may also include, if applicable, a discussion of certain U.S. federal income tax and U.K. income tax considerations.

GlaxoSmithKline Guarantees

Debt securities issued by the finance subsidiaries will be fully and unconditionally guaranteed by GlaxoSmithKline. If for any reason the applicable finance subsidiary does not make any required payment in respect of its debt securities when due, whether on the normal due date, on acceleration, redemption or otherwise,

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GlaxoSmithKline will cause the payment to be made to or to the order of the trustee. The holder of a guaranteed debt security will be entitled to payment under the applicable guarantee of GlaxoSmithKline without taking any action whatsoever against the finance subsidiary.

Payment and Transfer

The debt securities will be issued only as registered securities, which means that the name of the holder will be entered in a register that will be kept by the trustee or another agent appointed by us. Unless stated otherwise in a prospectus supplement, and except as described under “—Book-Entry System” below, payments of principal, interest and additional amounts, if any, will be made at the office of the paying agent or agents named in the prospectus supplement or by check mailed to you at your address as it appears in the register.

Unless other procedures are described in a prospectus supplement and except as described under “—Book Entry System” below, you will be able to transfer registered debt securities at the office of the transfer agent or agents named in the prospectus supplement. You may also exchange registered debt securities at the office of the transfer agent for an equal aggregate principal amount of registered debt securities of the same series having the same maturity date, interest rate and other terms as long as the debt securities are issued in authorized denominations.

Neither we nor the trustee will impose any service charge for any transfer or exchange of a debt security; however, we may ask you to pay any taxes or other governmental charges in connection with a transfer or exchange of debt securities.

Book-Entry System

Debt securities may be issued under a book-entry system in the form of one or more global securities. The global securities will be registered in the name of a depositary or its nominee and deposited with that depositary or its custodian. Unless stated otherwise in the prospectus supplement, The Depository Trust Company, New York, New York, or DTC, will be the depositary if a depositary is used.

DTC has advised us as follows:

According to DTC, the foregoing information with respect to DTC has been provided to the financial community for informational purposes only and is not intended to serve as a representation, warranty or contract modification of any kind.

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Following the issuance of a global security in registered form, the depositary will credit the accounts of its participants with the debt securities upon our instructions. Only persons who hold directly or indirectly through financial institutions that are participants in the depositary can hold beneficial interests in the global securities. Since the laws of some jurisdictions require certain types of purchasers to take physical delivery of such securities in definitive form, you may encounter difficulties in your ability to own, transfer or pledge beneficial interests in a global security.

So long as the depositary or its nominee is the registered owner of a global security, we and the trustee will treat the depositary as the sole owner or holder of the debt securities for purposes of the applicable indenture. Therefore, except as set forth below, you will not be entitled to have debt securities registered in your name or to receive physical delivery of certificates representing the debt securities. Accordingly, you will have to rely on the procedures of the depositary and the participant in the depositary through whom you hold your beneficial interest in order to exercise any rights of a holder under the indenture. We understand that under existing practices, the depositary would act upon the instructions of a participant or authorize that participant to take any action that a holder is entitled to take.

We will make all payments of principal, interest and additional amounts, if any, on the debt securities to the depositary. It is expected that the depositary will then credit participants’ accounts proportionately with these payments on the payment date and that the participants will in turn credit their customers’ accounts in accordance with their customary practices. Neither we nor the trustee will be responsible for making any payments to participants or customers of participants or for maintaining any records relating to the holdings of or payments to participants and their customers, and you will have to rely on the procedures of the depositary and its participants.

Global securities are generally not transferable. Physical certificates will be issued to beneficial owners in lieu of a global security only in the special situations described in the sixth paragraph under the heading “Legal Ownership of Debt Securities—Global Securities” above.

Consolidation, Merger or Sale

We and the finance subsidiaries have agreed in the indentures not to consolidate with or merge with or into any other person or convey or transfer all or substantially all of our respective properties and assets to any person (except that the finance subsidiaries may merge into us), unless:

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Covenants

Payment of Additional Amounts

Payments made by us under or with respect to the debt securities will be free and clear of and without withholding or deduction for or on account of any present or future tax, duty, levy, impost, assessment or other governmental charge of any nature whatsoever imposed or levied by or on behalf of (i) the government of the United Kingdom or of any territory of the United Kingdom or by any authority or agency therein or thereof having the power to tax or (ii) solely with respect to debt securities issued under the GSK Capital Inc. Indenture, the government of the United States or any state or territory of the United States or by any authority or agency therein or thereof having the power to tax, which we refer to collectively as “Taxes,” unless we are required to withhold or deduct Taxes by law.

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

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nor shall additional amounts be paid with respect to any payment of the principal of or interest on any debt security to any such holder who is a fiduciary or a partnership or a beneficial owner who is other than the sole beneficial owner of such payment to the extent a beneficiary or settlor with respect to such fiduciary or a member of such partnership or a beneficial owner would not have been entitled to such additional amounts had it been the holder of the debt security.

We have agreed in each indenture that at least one paying agent for each series of debt securities will be located outside the United Kingdom. We have also agreed that if we maintain a paying agent with respect to a particular series of debt securities in any member state of the European Union, we will maintain a paying agent in at least one member state (other than the United Kingdom) that will not be obliged to withhold or deduct taxes pursuant to any law implementing European Council Directive 2003/48/EC or any other Directive implementing the conclusions of the ECOFIN Council meeting of November 26-27, 2000 on the taxation of savings income, provided there is at least one member state that does not require a paying agent to withhold or deduct pursuant to such Directive.

Our obligation to pay additional amounts if and when due will survive the termination of the indentures and the payment of all amounts in respect of the debt securities.

Limitation on Liens

We have agreed in the indentures not to incur or assume (or permit any of our subsidiaries to incur or assume) any lien on or with respect to any of our or our subsidiaries’ property, assets or revenues, present or future, to secure any relevant indebtedness (as this term is defined below) without making (or causing our subsidiaries to make) effective provision for securing the debt securities equally and ratably with such relevant indebtedness as to such property, assets or revenues, for as long as such relevant indebtedness is so secured.

The restrictions on liens will not apply to:

For purposes of the limitation on liens covenant, the term “relevant indebtedness” means any of our debt that:

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Additional Covenants

We may be subject to additional covenants, including restrictive covenants in respect of a particular series of debt securities. Such additional covenants will be set forth in the applicable prospectus supplement and, to the extent necessary, in the supplemental indenture or board resolution relating to that series of debt securities.

Optional Redemption for Tax Reasons

We may redeem any series of debt securities in whole but not in part at any time, on giving not less than 30 nor more than 60 days’ notice of such redemption, at a redemption price equal to the principal amount plus accrued interest, if any, to the date fixed for redemption (except in the case of discounted debt securities, which may be redeemed at the redemption price specified by the terms of each series of such debt securities), if:

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We will also pay to each holder, or make available for payment to each such holder, on the redemption date any additional amounts resulting from the payment of such redemption price. Prior to the publication of any notice of redemption, we will deliver to the trustee:

Any notice of redemption will be irrevocable once we deliver the officer’s certificate to the trustee.

Events of Default

Unless otherwise specified in a prospectus supplement, an event of default with respect to a series of debt securities occurs upon:

Any additional or different events of default applicable to a particular series of debt securities will be described in the prospectus supplement relating to such series.

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

The trustee may withhold notice to the holders of debt securities of any default (except in the payment of principal, premium or interest) if it, in good faith, considers such withholding of notice to be in the best interests of the holders. A default is any event which is an event of default described above or would be an event of default but for the giving of notice or the passage of time.

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If an event of default occurs and continues, the trustee or the holders of the aggregate principal amount of the debt securities specified below may require us to repay immediately, or accelerate:

If the event of default occurs because of a default in a payment of principal or interest on the debt securities of any series, then the trustee or the holders of at least 25% of the aggregate principal amount of debt securities of that series can accelerate that series of debt securities. If the event of default occurs because of a failure to perform any other covenant in the applicable indenture or any covenant for the benefit of one or more, but not all, of the series of debt securities, then the trustee or the holders of at least 25% of the aggregate principal amount of debt securities of all series affected, voting as one class, can accelerate all of the affected series of debt securities. If the event of default occurs because of bankruptcy proceedings, then all of the debt securities under the indenture will be accelerated automatically. Therefore, except in the case of a default on a payment of principal or interest on the debt securities of your series or a default due to our bankruptcy or insolvency, it is possible that you may not be able to accelerate the debt securities of your series because of the failure of holders of other series to take action.

The holders of a majority of the aggregate principal amount of the debt securities of all affected series, voting as one class, can rescind this accelerated payment requirement or waive any past default or event of default or allow noncompliance with any provision of the applicable indenture. However, they cannot waive a default in payment of principal of, premium, if any, or interest on any of the debt securities when due otherwise than as a result of acceleration.

After an event of default, the trustee must exercise the same degree of care a prudent person would exercise under the circumstances in the conduct of her or his own affairs. Subject to these requirements, the trustee is not obligated to exercise any of its rights or powers under the applicable indenture at the request, order or direction of any holders, unless the holders offer the trustee indemnity satisfactory to it. If they provide this indemnity, the holders of a majority in principal amount of all affected series of debt securities, voting as one class, may direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any power conferred upon the trustee, for any series of debt securities. However, the trustee may refuse to follow any direction that conflicts with law or the indenture or is unduly prejudicial to the rights of other holders.

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

and during this 60-day period the holders of a majority in principal amount of all outstanding debt securities of such affected series do not give a direction to the trustee that is inconsistent with the enforcement request. These provisions will not prevent any holder of debt securities from enforcing payment of the principal of (and premium, if any) and interest on the debt securities at the relevant due dates.

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

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Modification of the Indentures

In general, rights and obligations of us and the holders under the indentures may be modified if the holders of a majority in aggregate principal amount of the outstanding debt securities of each series affected by the modification consent to such modification. However, each of the indentures provides that, unless each affected holder agrees, an amendment cannot:

However, if we and the trustee agree, the applicable indenture may be amended without notifying any holders or seeking their consent if the amendment does not materially and adversely affect any holder. We and the trustee are permitted to make modifications and amendments to the applicable indenture without the consent of any holder of debt securities for any of the following purposes:

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Defeasance

The term defeasance means discharge from some or all of the obligations under the indentures. If we deposit with the trustee sufficient cash or government securities to pay the principal, interest, any premium and any other sums due to the stated maturity date or a redemption date of the debt securities of a particular series, then at our option:

If this happens, the holders of the debt securities of the affected series will not be entitled to the benefits of the applicable indenture except for registration of transfer and exchange of debt securities and replacement of lost, stolen or mutilated debt securities. Instead, the holders will only be able to rely on the deposited funds or obligations for payment.

We must deliver to the trustee an opinion of counsel to the effect that the deposit and related defeasance would not cause the holders of the debt securities to recognize income, gain or loss for U.S. federal income tax purposes. We may, in lieu of an opinion of counsel, deliver a ruling to such effect received from or published by the U.S. Internal Revenue Service.

Substitution of Issuer

We may at our option at any time, without the consent of any holders of debt securities, cause GlaxoSmithKline or any other subsidiary of GlaxoSmithKline to assume the obligations of the applicable finance subsidiary under any series of debt securities, provided that the new obligor executes a supplemental indenture in which it agrees to be bound by the terms of those debt securities and the relevant indenture. If the new obligor is not a U.S. or U.K. company, it must be organized and validly existing under the laws of a jurisdiction that is a member country of the Organisation for Economic Cooperation and Development (or any successor) and it must also agree in the supplemental indenture to be bound by a covenant comparable to that described above under “—Covenants—Payment of Additional Amounts” with respect to taxes imposed in its jurisdiction of organization (in which case the new obligor will benefit from a redemption option comparable to that described above under “—Optional Redemption for Tax Reasons” in the event of changes in taxes in that jurisdiction after the date of the substitution). In the case of such a substitution, the applicable finance subsidiary will be relieved of any further obligation under the assumed series of debt securities.

For U.S. federal income tax purposes, a substitution of obligors as described above generally would be treated as a deemed taxable exchange of debt securities for new debt securities issued by the new obligor. As discussed further in the applicable prospectus supplement, a United States person who holds debt securities or owns a beneficial interest therein generally will recognize capital gain or loss in an amount equal to the difference between the issue price of the new debt securities and such person’s adjusted tax basis in the debt securities. Such persons should consult their own tax advisors regarding the tax consequences of a deemed taxable exchange in the event of a substitution of obligors.

Information Concerning the Trustee

Deutsche Bank Trust Company Americas, 60 Wall Street, 16th Floor, New York, NY 10005, will be the trustee. The trustee will be required to perform only those duties that are specifically set forth in the indentures, except when a default has occurred and is continuing with respect to the debt securities. After a default, the

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trustee must exercise the same degree of care that a prudent person would exercise under the circumstances in the conduct of her or his own affairs. Subject to these requirements, the trustee will be under no obligation to exercise any of the powers vested in it by the indentures at the request of any holder of debt securities unless the holder offers the trustee indemnity satisfactory to it against the costs, expenses and liabilities that might be incurred by exercising those powers.

Governing Law

The debt securities, the related guarantees and the indentures will be governed by and construed in accordance with the laws of the State of New York.

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TAX CONSIDERATIONS

The applicable prospectus supplement will describe certain U.K. tax considerations in connection with the acquisition, ownership and disposal of debt securities for investors who are not resident or (in the case of individuals) ordinarily resident in the United Kingdom for U.K. tax purposes at any material time (including Eligible U.S. Investors) and who meet certain other requirements. Such considerations will include whether the payment by us of principal (and premium, if any) and interest will be subject to U.K. withholding tax. For this purpose, “Eligible U.S. Investors” are investors who qualify for benefits under the income tax convention between the United States and the United Kingdom (the “Treaty”), who are residents of the United States for the purposes of the Treaty, and who are not resident or (in the case of individuals) ordinarily resident in the United Kingdom for U.K. tax purposes at any material time.

The applicable prospectus supplement also may describe certain U.S. federal income tax considerations relevant to a particular series of debt securities.

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