WAL Western Alliance Bancorporation

DESCRIPTION OF DEBENTURES

The debentures are a series of “subordinated debt securities” described in the accompanying prospectus. The debentures will be issued under a subordinated debt indenture to be dated as of June 16, 2016, as supplemented by a supplemental indenture to be dated as of the original issue date of the debentures, which we collectively refer to as the “Indenture,” between the Company and The Bank of New York Mellon Trust Company, N.A., as trustee, which we refer to as the “trustee.” Set forth below is a description of the specific terms of the debentures. Capitalized terms used but not defined herein shall have the respective meanings set forth in the Indenture. The following description does not purport to be complete and is subject to, and is qualified in its entirety by reference to, the description in the accompanying prospectus and the Indenture pursuant to which the debentures will be issued.

General

We will issue $175,000,000 aggregate principal amount of the debentures, or $200,000,000 aggregate principal amount if the underwriters exercise their over-allotment option in full, pursuant to the Indenture. The debentures are unsecured, subordinated debt instruments and are intended to qualify as Tier 2 Capital under the guidelines established by the Federal Reserve for bank holding companies. The debentures will be issued in fully-registered book-entry form without coupons and in denominations of $25 and integral multiples of $25 in excess thereof.

The debentures will have a maturity date of July 1, 2056.

Holders of the debentures and the trustee have no right to accelerate the maturity of the debentures in the event we fail to pay interest or principal on the debentures, fail to perform any other obligation under the debentures or in the Indenture or default on any other securities issued by us. See “Description of Debentures—Events of Default” below.

The Indenture does not require the maintenance of any financial ratios or specified levels of net worth or liquidity. The Indenture will not contain provisions that would afford holders of debentures protection in the event of a sudden and dramatic decline in our credit quality resulting from any highly leveraged transaction, reorganization, restructuring, merger or similar transaction involving us that may adversely affect holders. The Indenture does not restrict us in any way, now or in the future, from incurring additional indebtedness, including Senior Indebtedness (as defined below) that would rank senior in right of payment to the debentures.

The debentures will not be entitled to a sinking fund and cannot be redeemed at the option of the holder.

Interest Rate

Subject to applicable law, as described below, interest on the debentures will accrue from and including the original issue date to, but excluding, the maturity date or earlier acceleration or redemption at an annual rate equal to 6.25%, and will be payable quarterly July 1, October 1, January 1 and April 1 of each year, commencing on October 1, 2016, to the record holders at the close of business on the June 15, September 15, December 15 or March 15, as applicable (whether or not a Business Day). If the interest payment date falls on a day that is not a Business Day, interest will be paid on the next succeeding Business Day (and without any interest or other payment in respect of any such delay).

Interest payments will include accrued interest from, and including, the original issue date, or, if interest has already been paid, from and including the last date in respect of which interest has been paid or duly provided for to, but excluding, the next succeeding interest payment date, the maturity date or the redemption date, as the case may be. The amount of interest payable for any interest payment period will be computed on the basis of a 360-day year comprised of twelve 30-day months. The term “interest payment period” refers to the quarterly period from and including an interest payment date (or, if no interest has been paid, from and including the original issue date) to, but excluding, the next succeeding interest payment date. Interest not paid on any payment date

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will accrue and compound quarterly at a rate per year equal to the rate of interest on the debentures until paid. References to “interest” include interest accruing on the debentures, interest on unpaid amounts and compounded interest, as applicable.

We may choose to pay interest by making wire or other electronic funds transfers or alternatively, by mailing a check to the address of the person entitled thereto as it appears in the Security Register.

“Business day” means any day which is not a Saturday, a Sunday, a legal holiday in New York, New York or a day on which banking institutions or trust companies located in New York, New York are authorized or obligated by law to close.

Ranking

The payment of the principal of and interest on the debentures will be expressly subordinated, to the extent and in the manner set forth in the Indenture, to the prior payment in full of all of our Senior Indebtedness.

“Senior Indebtedness” is defined to include principal of (and premium, if any) and interest, if any, on, and any other payment due pursuant to, any of the following:

unless, in any case, in the instrument creating or evidencing any such indebtedness or obligation, or pursuant to which the same is outstanding, it is expressly provided that such indebtedness or obligation is not superior in right of payment to the debentures or to other debt that is pari passu with or subordinate to the debentures.

Senior Indebtedness will not include:

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“General Obligations” are defined as all of our obligations to pay claims of general creditors, other than obligations on the debentures and our indebtedness for money borrowed ranking equally or subordinate to the debentures. Notwithstanding the foregoing, if the Federal Reserve (or other competent regulatory agency or authority) promulgates any rule or issues any interpretation that defines general creditor(s) the main purpose of which is to establish a criteria for determining whether the subordinated debt of a bank holding company is to be included in its capital, then the term “General Obligations” will mean obligations to general creditors as described in that rule or interpretation.

The term claim when used in the previous definition has the meaning stated in section 101(5) of Title 11 of the United States Code, as now or hereafter in effect.

In addition, the debentures will be structurally subordinated to all existing and future indebtedness, liabilities and other obligations, including deposits, of our subsidiaries. Because we are a bank holding company, we rely primarily on dividends and other payments from our subsidiaries to pay interest and principal on our outstanding debt obligations and to make payments on our other securities. Regulatory rules restrict our ability to withdraw capital from Western Alliance Bank by dividends, loans or other means. See “Risk Factors—We are a bank holding company and, therefore, may not be able to receive dividends in amounts needed to service our debt.”

If certain events in bankruptcy, insolvency or reorganization occur, we will first pay all Senior Indebtedness, including any interest accrued after the events occur, in full before we make any payment or distribution, whether in cash, securities or other property, on account of the principal of or interest on the debentures. In such an event, we will pay or deliver directly to the holders of Senior Indebtedness, any payment or distribution otherwise payable or deliverable to holders of the debentures. We will make the payments to the holders of Senior Indebtedness according to priorities existing among those holders until we have paid all Senior Indebtedness, including accrued interest, in full. If, notwithstanding the preceding sentence, the trustee or the holder of any debenture receives any payment or distribution before all Senior Indebtedness is paid in full, and if such fact shall, at or prior to the time of such payment or distribution, have been made known to the trustee or such holder, then such payment or distribution shall be paid over or delivered for application to the payment of all Senior Indebtedness remaining unpaid, to the extent necessary to pay all Senior Indebtedness in full, after giving effect to any concurrent payment or distribution to or for the holders of Senior Indebtedness.

If such events of bankruptcy, insolvency or reorganization occur, after we have paid in full all amounts owed on Senior Indebtedness, the holders of debentures together with the holders of any of our other obligations that rank equally with the debentures will be entitled to receive from our remaining assets any principal, premium or interest due at that time on the debentures and such other obligations before we make any payment or other distribution on account of any of our capital stock or obligations ranking junior to the debentures. See “Risk Factors—Government regulation may affect the priority of the debentures in the case of a bankruptcy or liquidation.”

In addition, if any principal, premium or interest in respect of Senior Indebtedness is not paid within any applicable grace period (including at maturity) or any other default on Senior Indebtedness occurs and the maturity of such Senior Indebtedness is accelerated in accordance with its terms, we may not pay the principal of, or premium, if any, or interest on, the debentures or repurchase, redeem or otherwise retire any debentures, unless, in each case, the default has been cured or waived and any such acceleration has been rescinded or such Senior Indebtedness has been paid in full in cash, subject to certain exceptions as provided in the Indenture. If the debentures are declared due and payable before their stated maturity, the holders of Senior Indebtedness outstanding at the time the debentures so become due and payable shall be entitled to receive payment in full of all amounts due or to become due on or in respect of such Senior Indebtedness before the holders of the debentures are entitled to receive any payment on the debentures. If, notwithstanding the foregoing, we make any payment to the trustee or the holder of any debenture prohibited by the preceding sentences, and if such fact

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shall, at or prior to the time of such payment, have been made known to the trustee or such holder, such payment must be paid over and delivered to us.

Because of the subordination provisions of the Indenture, if we become insolvent, holders of Senior Indebtedness may receive more, ratably, and holders of the debentures may receive less, ratably, than our other creditors.

The debentures do not limit our or our subsidiaries’ ability to incur additional debt, including debt that ranks senior or pari passu (i) in right of payment and (ii) upon our liquidation to the debentures. At March 31, 2016, we had $153.2 million of indebtedness ranking senior to the debentures, no indebtedness ranking equally with the debentures and $57.2 million of indebtedness ranking junior to the debentures. The debentures will be effectively subordinated to all of the existing and future indebtedness and other liabilities of our subsidiaries, including Western Alliance Bank’s 5.00% Fixed-to-Floating Rate Subordinated Notes due July 15, 2025. At March 31, 2016, Western Alliance Bank and our other subsidiaries had outstanding indebtedness, total deposits and other liabilities of $13.55 billion, excluding intercompany liabilities, all of which ranks structurally senior to the debentures.

Optional Redemption

We may redeem the debentures in $25 increments in whole or in part on July 1, 2021, or on any interest payment date thereafter, at a redemption price equal to 100% of the principal amount of the debentures being redeemed plus accrued and unpaid interest to, but not including, the date of redemption. If we redeem only a portion of the debentures on any date of redemption, we may subsequently redeem additional debentures.

The debentures are also redeemable by us, in whole but not in part, at a redemption price equal to 100% of the principal amount of the debentures plus accrued and unpaid interest to, but excluding, the date of redemption, upon the occurrence of the following:

(i) a “tax event,” which means the receipt by us of an opinion of independent tax counsel of nationally recognized standing to the effect that, as a result of any:

in each case, occurring, enacted or becoming publicly known on or after the date of the issuance of the debentures, there is more than an insubstantial risk that the interest payable on the debentures is not, or within 90 days of receipt of such opinion of tax counsel, will not be, deductible by us, in whole or in part, for U.S. federal income tax purposes;

(ii) a “capital event,” which means the receipt by us of an opinion of independent bank regulatory counsel to the effect that, as a result of (a) any amendment to, or change (including any announced prospective change) in, the laws or any regulations thereunder of the United States or any rules, guidelines or policies of an applicable regulatory authority for us or (b) any official administrative pronouncement or judicial decision

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interpreting or applying such laws or regulations, which amendment or change is effective or which pronouncement or decision is announced on or after the date of original issuance of the debentures, the debentures do not constitute, or within 90 days of the date of such opinion will not constitute, Tier 2 capital (or its then equivalent if we are subject to such capital requirement) for purposes of capital adequacy guidelines of the Federal Reserve (or any successor regulatory authority with jurisdiction over bank holding companies), as then in effect and applicable to us; or

(iii) an “investment company event,” which means us becoming required to register as an investment company pursuant to the Investment Company Act of 1940, as amended.

Notice of any redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each holder of debentures to be redeemed at its registered address, provided that the notice of redemption will be given within 90 days of the effective date of a tax event, capital event or investment company event. Unless we default in payment of the redemption price on the debentures, on and after the redemption date, interest will cease to accrue on the debentures or portions called for redemption.

Under the Federal Reserve’s current risk-based capital guidelines applicable to bank holding companies, any redemption of the debentures will be subject to prior approval of the Federal Reserve.

Redemption Procedures

If we give a notice of redemption in respect of any debentures, then prior to the redemption date, we will:

Notwithstanding the above, interest payable on or prior to the redemption date for any debentures called for redemption will be payable to the holders of the debentures on the relevant record dates for the related interest payment dates.

Once notice of redemption has been given and funds deposited as required, then upon the date of the deposit, all rights of the holders of the debentures so called for redemption will cease, except the right of the holders of the debentures to receive the redemption price and any interest payable in respect of the debentures on or prior to the redemption date and the debentures will cease to be outstanding. In the event that any date fixed for redemption of debentures is not a business day, then payment of the redemption price will be made on the next business day (without any interest or other payment in connection with this delay) with the same force and effect as if made on the original date. In the event that payment of the redemption price in respect of debentures called for redemption is not paid by us, interest on the debentures will continue to accrue at the then applicable rate from the redemption date originally established by us for the debentures to the date the redemption price is actually paid, in which case the actual payment date will be the date fixed for redemption for purposes of calculating the redemption price.

Subject to applicable law (including, without limitation, U.S. federal securities law), we or our subsidiaries may at any time and from time to time purchase outstanding debentures by tender, in the open market or by private agreement.

If less than all of the debentures are to be redeemed, the particular debentures to be redeemed will be determined, in the case of global securities, in accordance with the procedures of the depositary and, in the case

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of definitive debt securities, by the trustee by such method as in its sole discretion it shall deem appropriate and fair, provided that the unredeemed portion of the principal amount of any debenture shall be in an authorized denomination (which shall not be less than the minimum authorized denomination) for such debenture. The trustee will promptly notify us in writing of the debentures selected for redemption and, in the case of any debentures selected for partial redemption, the principal amount thereof to be redeemed.

We may not redeem the debentures in part if the principal amount has been accelerated and such acceleration has not been rescinded or unless all accrued and unpaid interest, has been paid in full on all outstanding debentures for all interest payment periods terminating on or before the redemption date.

Denominations

The debentures will be issued only in fully-registered book-entry form without coupons in denominations of $25 each and integral multiples of $25 in excess thereof.

Events of Default

The Indenture will provide that certain events of bankruptcy, insolvency or receivership relating to us or a “principal subsidiary bank” are events of default with respect to the debentures.

The term “principal subsidiary bank” means (i) any bank subsidiary the consolidated assets of which constitute 25% or more of our consolidated assets and (ii) any other bank subsidiary designated as a “principal subsidiary bank” by our Board of Directors; provided that if the Federal Reserve notifies us that any bank subsidiary that is a principal subsidiary bank applying the tests in clause (i) or (ii) above does not qualify as a “major subsidiary depository institution” within the requirements of the Federal Reserve’s risk-based capital guidelines applicable to bank holding companies, such bank subsidiary will not be a principal subsidiary bank from and after the time we receive from the Federal Reserve such a notice. Currently, Western Alliance Bank is our only principal subsidiary bank.

The Indenture will define a default with respect to the debentures as:

There is only a right of acceleration in the case of an event of default. There is no right of acceleration in the case of a default. Accordingly, payment of principal of the debentures may be accelerated only in the case of the bankruptcy or reorganization of us or any principal subsidiary bank. Notwithstanding the foregoing, in the case of a default in the payment of principal of or interest on the debentures including any compound interest, the holder of a debenture may, or, if directed by the holders of a majority in principal amount of the debentures, the trustee will, subject to the conditions set forth in the indenture, demand payment of the amount then due and payable and may institute legal proceedings for the collection of such amount if we fail to make payment thereof upon demand.

If an event of default occurs and is continuing with respect to the debentures, either the trustee or the holders of at least 25% in principal amount of the debentures may declare the principal of the debentures to be due and payable immediately. Subject to certain conditions, the holders of a majority in principal amount of the debentures may rescind such declaration.

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In cases specified in the Indenture, the holders of a majority in principal amount of the debentures may waive any default on behalf of all holders of the debentures, except a default in the payment of principal or interest or a default in the performance of a covenant or provision of the Indenture which cannot be modified without the consent of each holder. We are required to file annually with the trustee a certificate as to whether or not we are in compliance with all the conditions and covenants applicable to us under the Indenture.

Within 90 days after the trustee’s knowledge of the occurrence of any default with respect to the debentures, the trustee shall transmit by mail to all holders of debentures, notice of such default unless such default shall have been cured or waived.

The holders of a majority of the aggregate outstanding principal amount of the debentures have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee with respect to the debentures.

Consolidation, Merger or Transfer of Assets

The Company may not, in a single transaction or through a series of related transactions, consolidate with or merge with or into any other Person, or, directly or indirectly, sell, transfer or convey all or substantially all of its properties and assets to another Person or group of affiliated Persons, unless:

Modification and Waiver

Without the consent of any holders, the Company and the trustee, at any time and from time to time, may amend the Indenture for any of the following purposes:

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With the consent of the holders of not less than a majority in principal amount of the debentures (including consents obtained in connection with a tender offer or exchange offer for the debentures), the Company and the trustee may amend the Indenture for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of the Indenture or of modifying in any manner the rights of the holders of the debentures; provided , however , that no such amendment shall, without the consent of the holder of each debenture affected thereby,

Satisfaction and Discharge

We may satisfy and discharge our obligations under the debentures and the Indenture (except with respect to the registration of transfer or exchange of the debentures), if either

Defeasance and Covenant Defeasance

Defeasance

We may terminate or “defease” our obligations under the Indenture with respect to the debentures, provided that certain conditions are met, including:

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If we ever fully defease the debentures, holders will have to rely solely on the trust deposit for payments on the debentures. Holders could not look to us for repayment in the unlikely event of any shortfall.

Covenant Defeasance

The “covenant defeasance” provisions of the Indenture, which would allow us to cease to comply with any restrictive covenants applicable to the debentures, are not applicable to the debentures because there are no restrictive covenants applicable to the debentures.

Governing Law

The Indenture and the debentures will be governed by and construed in accordance with the laws of the State of New York. The Indenture will be subject to the provisions of the Trust Indenture Act of 1939, as amended.

Listing

We intend to apply to list the debentures on the New York Stock Exchange under the symbol “WALA.” If the application is approved, we expect trading on the New York Stock Exchange to begin within 30 days of the original issue date of the debentures.

Debentures Intended to Qualify as Tier 2 Capital

The debentures are intended to qualify as Tier 2 Capital under the capital rules established by the Federal Reserve for bank holding companies that became effective January 1, 2014. The rules set forth specific criteria for instruments to qualify as Tier 2 Capital. Among other things, the debentures must:

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Further Issuances

We may, from time to time, without the consent of the holders of the debentures, create and issue additional notes having the same terms and conditions as the debentures that are equal in rank to the debentures offered by this prospectus supplement in all respects (or in all respects except for the issue date, the issue price and, if applicable, the first interest payment date and the initial interest accrual date). These notes will be consolidated and form a single series with the debentures, provided , however , that a separate CUSIP, common code or ISIN, as applicable, will be issued for any additional notes unless the additional notes and the debentures of such series offered under this prospectus supplement are fungible for U.S. federal income tax purposes.

About the Trustee

The Bank of New York Mellon Trust Company, N.A. is the trustee under the Indenture and will be the principal paying agent and registrar for the debentures. We have entered, and from time to time may continue to enter, into banking or other relationships with The Bank of New York Mellon Trust Company, N.A. or its affiliates.

The trustee under the Indenture may resign or be removed with respect to one or more series of debt securities under the Indenture and a successor trustee may be appointed to act with respect to such series.

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BOOK-ENTRY SYSTEM—THE DEPOSITORY TRUST COMPANY

Upon issuance, the debentures will be represented by one or more fully registered global certificates, each of which we refer to as a global security. Each such global security will be deposited with, or on behalf of, The Depository Trust Company (“DTC”) and registered in the name of DTC or a nominee thereof. Initial settlement for the debentures will be made in same day funds. Secondary market trading between DTC participants will occur in the ordinary way in accordance with DTC’s rules. Unless and until it is exchanged in whole or in part for debentures in definitive form, no global security may be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any such nominee to a successor of DTC or a nominee of such successor.

Beneficial interests in the debentures will be represented through book-entry accounts of financial institutions acting on behalf of beneficial owners as direct and indirect participants in DTC.

So long as DTC, or its nominee, is a registered owner of a debenture, DTC or its nominee, as the case may be, will be considered the sole owner or holder of the debentures represented by such debenture for all purposes under the Indenture. Except as provided below, the actual owners of the debentures represented by a debenture (the “beneficial owner”) will not be entitled to have the debentures represented by such debenture registered in their names, will not receive or be entitled to receive physical delivery of the debentures in definitive form and will not be considered the owners or holders thereof under the Indenture.

If DTC is at any time unwilling or unable to continue as depositary and a successor depositary is not appointed by us within 90 days, we will issue debentures in definitive form in exchange for the global notes. We will also issue debentures in definitive form in exchange for the global notes if an event of default or default has occurred with regard to the debentures represented by the global notes and has not been cured or waived. In addition, we may at any time and in our sole discretion (subject to the procedures of DTC) determine not to have the debentures represented by the global notes and, in that event, will issue debentures in definitive form in exchange for the global notes. In any such instance, an owner of a beneficial interest in the global notes will be entitled to physical delivery in definitive form of debentures represented by the global notes equal in principal amount to such beneficial interest and to have such debentures registered in its name. Debentures so issued in definitive form will be issued as registered debentures in denominations of $25 and integral multiples of $25 above that amount, unless otherwise specified by us. debentures in definitive form can be transferred by presentation for registration to the registrar at its New York offices and must be duly endorsed by the holder or his attorney duly authorized in writing, or accompanied by a written instrument or instruments of transfer in form satisfactory to us or the trustee duly executed by the holder or his attorney duly authorized in writing. We may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in

Accordingly, each person owning a beneficial interest in a debenture must rely on the procedures of DTC and, if such person is not a participant of DTC (a “participant”), on the procedures of the participant through which such person owns its interest, to exercise any rights of a holder under the Indenture. We understand that under existing industry practices, in the event that the Company requests any action of holders of the debentures or that an owner of a beneficial interest is entitled to give or take under the Indenture, DTC would authorize the participants holding the relevant beneficial interests to give or take such action, and such participants would authorize beneficial owners owning through such participants to give or take such action or would otherwise act upon the instructions of beneficial owners. Conveyance of notices and other communications by DTC to participants, by participants to indirect participants, as defined below, and by participants and indirect 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 following is based on information furnished by DTC:

DTC will act as securities depositary for the debentures. Offered securities will be issued as fully registered securities registered in the name of Cede & Co. (DTC’s partnership nominee). One or more fully registered global securities will be issued for the debentures, and will be deposited with DTC.

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DTC is a limited-purpose trust company organized under the New York Banking Law, a “banking organization” within the meaning of the New York Banking Law, a member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code, and a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act. DTC holds securities that its participants deposit with DTC. DTC also facilitates the settlement among participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in participants’ accounts, thereby eliminating the need for physical movement of securities certificates. Direct participants of DTC (“direct participants”) include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. DTC is owned by a number of its direct participants and by the NYSE, the American Stock Exchange, Inc. and FINRA. Access to DTC’s system is also available to others such as securities brokers and dealers, banks and trust companies that clear through or maintain a custodial relationship with a direct participant, either directly or indirectly (“indirect participants”). The rules applicable to DTC and its participants are on file with the SEC.

Purchases of the debentures under DTC’s system must be made by or through direct participants, which will receive a credit for the debentures on DTC’s records. The ownership interest of each beneficial owner is in turn to be recorded on the records of direct participants and indirect participants. Beneficial owners 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 participants or indirect participants through which such beneficial owner entered into the transaction. Transfers of ownership interests in the debentures are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the debentures, except in the limited circumstances that may be provided in the Indenture.

To facilitate subsequent transfers, all debentures deposited with DTC are registered in the name of DTC’s partnership nominee, Cede & Co. The deposit of the debentures with DTC and their registration in the name of Cede & Co. effect no change in beneficial ownership. DTC has no knowledge of the actual beneficial owners of the debentures. DTC’s records reflect only the identity of the direct participants to whose accounts such securities are credited, which may or may not be the beneficial owners. The 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 participants, by direct participants to indirect participants, and by direct participants and indirect 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.

Neither DTC nor Cede & Co. will consent or vote with respect to the debentures. Under its usual procedures, DTC mails an Omnibus Proxy to the Company as soon as possible after the applicable record date. The Omnibus Proxy assigns Cede & Co.’s consenting or voting rights to those direct participants to whose accounts securities are credited on the applicable record date (identified in a listing attached to the Omnibus Proxy).

Payments on the debentures will be made in immediately available funds to DTC. DTC’s practice is to credit direct participants’ accounts on the applicable payment date in accordance with their respective holdings shown on DTC’s records unless DTC has reason to believe that it will not receive payment on such date. 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 in bearer form or registered in “street name,” and will be the responsibility of such participant and not of DTC, the trustee under the Indenture or the Company, subject to any statutory or regulatory requirements as may be in effect from time to time. Any payment due to DTC on behalf of beneficial owners is the responsibility of the Company or the applicable agent, disbursement of such payments to direct participants shall be the responsibility of DTC, and disbursement of such payments to the beneficial owners shall be the responsibility of direct participants and indirect participants.

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DTC may discontinue providing its services as securities depositary with respect to the debentures at any time by giving reasonable notice to the Company or the applicable agent. Under such circumstances, in the event that a successor securities depositary is not obtained, offered security certificates are required to be printed and delivered. The Company may decide (subject to the procedures of DTC) to discontinue use of the system of book-entry transfers through DTC (or a successor securities depositary). In that event, offered security certificates will be printed and delivered.

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DESCRIPTION OF DEBT SECURITIES

General

We may issue senior debt securities and/or subordinated debt securities, which in each case will be unsecured, direct, general obligations of Western Alliance.

The senior debt securities will rank equally with all our other unsecured and unsubordinated debt. The subordinated debt securities will be subordinate and junior in priority of payment to our senior debt securities, as described below under “Ranking–Subordination of Subordinated Debt Securities” and in the prospectus supplement applicable to any subordinated debt securities that we may offer. For purposes of the descriptions in this section, we may refer to the senior debt securities and the subordinated debt securities collectively as the “debt securities.” The debt securities will be effectively subordinated to the creditors and preferred equity holders of our subsidiaries.

We will issue senior debt securities under a senior debt indenture and subordinated debt securities under a separate subordinated debt indenture. Provisions relating to the issuance of debt securities may also be set forth in a supplemental indenture to either of the indentures. For purposes of the descriptions in this section, we may refer to the senior debt indenture and the subordinated debt indenture and any related supplemental indentures, as “an indenture” or, collectively, as “the indentures.” The indentures will be qualified under and governed by the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”).

Each indenture will be between us and a trustee that meets the requirements of the Trust Indenture Act. We expect that each indenture will provide that there may be more than one trustee under that indenture, each with respect to one or more series of debt securities. Any trustee under an indenture may resign or be removed with respect to one or more series of debt securities and, in that event, we may appoint a successor trustee. Except as otherwise provided in the indenture or supplemental indenture, any action permitted to be taken by a trustee may be taken by that trustee only with respect to the one or more series of debt securities for which it is trustee under the applicable indenture.

The descriptions in this section relating to the debt securities and the indentures are summaries of their provisions. The summaries are not complete and are qualified in their entirety by reference to the actual indentures and debt securities and the further descriptions in the applicable prospectus supplement. A form of the senior debt indenture and a form of the subordinated debt indenture under which we may issue our senior debt securities and subordinated debt securities, respectively, and the forms of the debt securities, have been filed with the SEC as exhibits to the registration statement that includes this prospectus and will be available as described under the heading “Where You Can Find More Information” above. Whenever we refer in this prospectus or in any prospectus supplement to particular sections or defined terms of an indenture, those sections or defined terms are incorporated by reference in this prospectus or in the prospectus supplement, as applicable. You should refer to the provisions of the indentures for provisions that may be important to you.

The terms and conditions described in this section are terms and conditions that apply generally to the debt securities. The particular terms of any series of debt securities will be summarized in the applicable prospectus supplement. Those terms may differ from the terms summarized below.

Except as set forth in the applicable indenture or in a supplemental indenture and described in an applicable prospectus supplement, the indentures do not limit the amount of debt securities we may issue under the indentures. We are not required to issue all of the debt securities of one series at the same time and, unless otherwise provided in the applicable indenture or supplemental indenture and described in the applicable prospectus supplement, we may, from time to time, reopen any series and issue additional debt securities under that series without the consent of the holders of the outstanding debt securities of that series. Additional notes issued in this manner will have the same terms and conditions as the outstanding debt securities of that series, except for their original issue date and issue price, and will be consolidated with, and form a single series with, the previously outstanding debt securities of that series.

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Terms of Debt Securities to be Included in the Prospectus Supplement

The prospectus supplement relating to any series of debt securities that we may offer will set forth the price or prices at which the debt securities will be offered, and will contain the specific terms of the debt securities of that series. These terms may include, without limitation, the following:

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Unless otherwise specified in the applicable prospectus supplement, the debt securities will not be listed on any securities exchange.

We may offer and sell our debt securities at a substantial discount below their stated principal amount. These debt securities may be original issue discount securities, which means that less than the entire principal amount of the original issue discount securities will be payable upon declaration of acceleration of their maturity. Special federal income tax, accounting and other considerations applicable to original issue discount securities will be described in the applicable prospectus supplement.

We may issue debt securities with a fixed interest rate or a floating interest rate. Any material federal income tax considerations applicable to any discounted debt securities or to debt securities issued at par that are treated as having been issued at a discount for federal income tax purposes will be described in the applicable prospectus supplement.

Except as set forth in the applicable indenture or in a supplemental indenture, the debt securities will not contain any provisions that would limit our ability to incur indebtedness or that would afford holders of debt securities protection in the event of a highly leveraged or similar transaction involving us. The debt securities may contain provisions that would afford debt security holders protection in the event of a change of control. You should refer to the applicable prospectus supplement for information with respect to any deletions from, modifications of or additions to the events of default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

For purposes of the descriptions in this section:

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Ranking

Senior Debt Securities

Payment of the principal of and premium, if any, and interest on debt securities we issue under the senior debt indenture will rank equally with all of our unsecured and unsubordinated debt.

Subordination of Subordinated Debt Securities

To the extent provided in the subordinated debt indenture and any supplemental indenture, and as described in the prospectus supplement describing the applicable series of subordinated debt securities, the payment of the principal of and premium, if any, and interest on any subordinated debt securities, including amounts payable on any redemption or repurchase, will be subordinated in right of payment and junior to senior debt, which is defined below. If there is a distribution to our creditors in a liquidation or dissolution of us, or in a bankruptcy, reorganization, insolvency, receivership or similar proceeding relating to us, the holders of senior debt will first be entitled to receive payment in full of all amounts due on the senior debt (or provision shall be made for such payment in cash) before any payments may be made on the subordinated debt securities. Because of this subordination, our general creditors may recover more, ratably, than holders of subordinated debt securities in the event of a distribution of assets upon insolvency.

The supplemental indenture will set forth the terms and conditions under which, if any, we will not be permitted to pay principal, premium, if any, or interest on the related subordinated debt securities upon the occurrence of an event of default or other circumstances arising under or with respect to senior debt.

The indentures will place no limitation on the amount of senior debt that we may incur. We expect to incur from time to time additional indebtedness constituting senior debt, which may include indebtedness that is senior to the subordinated debt securities but subordinate to our other obligations.

“Senior debt” means the principal of, and premium, if any, and interest, including interest accruing after the commencement of any bankruptcy proceeding relating to us, on, or substantially similar payments we will make in respect of the following categories of debt, whether that debt is outstanding at the date of execution of the applicable indenture or thereafter incurred, created or assumed:

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However, “senior debt” excludes:

As used above, the term “purchase money obligations” means indebtedness, obligations or guarantees evidenced by a note, debenture, bond or other instrument, whether or not secured by a lien or other security interest, and any deferred obligation for the payment of the purchase price of property but excluding indebtedness or obligations for which recourse is limited to the property purchased, issued or assumed as all or a part of the consideration for the acquisition of property or services, whether by purchase, merger, consolidation or otherwise, but does not include any trade accounts payable. There will not be any restrictions in the subordinated indenture relating to subordinated debt securities upon the creation of additional senior debt.

The applicable prospectus supplement may further describe the provisions, if any, applicable to the subordination of the subordinated debt securities of a particular series. The applicable prospectus supplement or the information incorporated by reference in the applicable prospectus supplement or in this prospectus will describe as of a recent date the approximate amount of our senior debt outstanding as to which the subordinated debt securities of that series will be subordinated.

Structural Subordination

Because we are a holding company, our cash flows and consequent ability to service our obligations, including our debt securities, are dependent on distributions and other payments of earnings and other funds by our subsidiaries to us. The payment of dividends and other distributions by our subsidiaries is contingent on their earnings and is subject to the requirements of federal banking regulations and other restrictions. In addition, the debt securities will be structurally subordinated to all indebtedness and other liabilities of our subsidiaries, since our right to receive any assets of its subsidiaries upon their liquidation or reorganization, and the consequent right of the holders of the debt securities to participate in those assets, will be effectively subordinated to the claims of that subsidiary’s creditors. If we are recognized as a creditor of that subsidiary, our claims would still be subordinate to any security interest in the assets of that subsidiary and any indebtedness of that subsidiary senior to that held by us. Claims from creditors (other than us), on subsidiaries may include long-term and medium-term debt and substantial obligations related to deposit liabilities, federal funds purchased, securities sold under repurchase agreements and other short-term borrowings. Any capital loans that we make to our non-banking subsidiaries would be subordinate in right of payment to deposits and to other indebtedness of WAB or our non-banking subsidiaries.

Conversion or Exchange of Debt Securities

The applicable prospectus supplement will set forth the terms, if any, on which a series of debt securities may be converted into or exchanged for our other securities. These terms will include whether conversion or exchange is mandatory, or is at our option or at the option of the holder. We will also describe in the applicable

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prospectus supplement how we will calculate the number of securities that holders of debt securities would receive if they were to convert or exchange their debt securities, the conversion price and other terms related to conversion and any anti-dilution protections.

Redemption of Securities

We may redeem the debt securities at any time, in whole or in part, at the prescribed redemption price, at the times and on the terms described in the applicable prospectus supplement.

From and after notice has been given as provided in the indentures, if we have made available funds for the redemption of any debt securities called for redemption on the applicable redemption date, the debt securities will cease to bear interest on the date fixed for the redemption specified in the notice, and the only right of the holders of the debt securities will be to receive payment of the redemption price.

Notice of any optional redemption by us of any debt securities is required to be given to holders at their addresses, as shown in the security register. The notice of redemption will be required to specify, among other items, the redemption price and the principal amount of the debt securities held by the holder to be redeemed.

If we elect to redeem debt securities, we will be required to notify the trustee of the aggregate principal amount of debt securities to be redeemed and the redemption date. If fewer than all the debt securities are to be redeemed, the trustee is required to select the debt securities to be redeemed equally, by lot or in a manner it deems fair and appropriate.

Denomination, Interest, Registration and Transfer

Unless otherwise specified in the applicable prospectus supplement, we will issue the debt securities (i) in denominations of $1,000 or integral multiples of $1,000 if the debt securities are in registered form, and (ii) in denominations of $5,000 if the debt securities are in bearer form.

Unless otherwise specified in the applicable prospectus supplement, we will pay the principal of, and applicable premium, if any, and interest on any series of debt securities at the corporate trust office of the trustee, the address of which will be stated in the applicable prospectus supplement. At our option, we may pay interest by check mailed to the address of the person entitled to the interest payment as it appears in the register for the applicable debt securities or by wire transfer of funds to that person at an account maintained within the United States.

Any defaulted interest, which means interest not punctually paid or duly provided for on any interest payment date with respect to a debt security, will immediately cease to be payable to the registered holder on the applicable regular record date by virtue of his having been the registered holder on such date. We may pay defaulted interest either to the person in whose name the debt security is registered at the close of business on a special record date for the payment of the defaulted interest to be fixed by the trustee, notice of which is to be given to the holder of the debt security not less than ten days before the special record date, or at any time in any other lawful manner, all as more completely described in the applicable indenture or supplemental indenture.

Subject to limitations imposed upon debt securities issued in book-entry form, the holder may exchange debt securities of any series for other debt securities of the same series and of a like aggregate principal amount and tenor of different authorized denominations upon surrender of the debt securities at the corporate trust office of the applicable trustee. In addition, subject to limitations imposed upon debt securities issued in book-entry form, the holder may surrender debt securities of any series for registration of transfer or exchange at the corporate trust office of the applicable trustee. Every debt security surrendered for registration of transfer or exchange must be duly endorsed or accompanied by a written instrument of transfer. No service charge will be imposed for any registration of transfer or exchange of any debt securities, but we may require payment of a sum

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sufficient to cover any tax or other governmental charge payable in connection with any registration of transfer or exchange of any debt securities. If the applicable prospectus supplement refers to any transfer agent, in addition to the applicable trustee, initially designated by us with respect to any series of debt securities, we may at any time rescind the designation of that transfer agent or approve a change in the location through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for that series. We may at any time designate additional transfer agents with respect to any series of debt securities.

If we redeem the debt securities of any series, neither we nor any trustee will be required to:

Global Securities

We may issue the debt securities of a series in whole or in part in the form of one or more global securities to be deposited with, or on behalf of, a depository or with a nominee for a depository identified in the applicable prospectus supplement relating to that series. We may issue global securities in either registered or bearer form and in either temporary or permanent form. The specific terms of the depository arrangement with respect to a series of debt securities will be described in the prospectus supplement relating to that series.

Our obligations with respect to the debt securities, as well as the obligations of the applicable trustee, run only to persons who are registered holders of debt securities. For example, once we make payment to the registered holder, we have no further responsibility for that payment even if the recipient is legally required to pass the payment along to an individual investor but fails to do so. As an indirect holder, an investor’s rights relating to a global security will be governed by the account rules of the investor’s financial institution and of the depositary, as well as general laws relating to transfers of debt securities.

An investor should be aware that when debt securities are issued in the form of global securities:

The applicable prospectus supplement for a series of debt securities will list the special situations, if any, in which a global security will terminate and interests in the global security will be exchanged for physical certificates representing debt securities. After that exchange, the investor may choose whether to hold debt securities directly or indirectly through an account at the investor’s bank or brokerage firm. In that event,

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investors must consult their banks or brokers to find out how to have their interests in debt securities transferred to their own names so that they may become direct holders. When a global security terminates, the depositary, and not us or one of the trustees, is responsible for deciding the names of the institutions that will be the initial direct holders.

Merger, Consolidation or Sale of Assets

We will not be permitted to consolidate with or merge into any other entity, or sell, lease, transfer or convey all or substantially all of our properties and assets, either in one transaction or a series of transactions, to any other entity and no other entity will consolidate with or merge into us, or sell, lease, transfer or convey all or substantially all of its properties and assets to us unless:

Except as provided in this prospectus or as may otherwise be provided in the applicable prospectus supplement, the indenture and the terms of the debt securities will not contain any event risks or similar covenants that are intended to afford protection to holders of any debt securities in the event of a merger, a highly leveraged transaction or other significant corporate event involving us or our subsidiaries, whether or not resulting in a change of control, which may adversely affect holders of the debt securities.

Additional Covenants and/or Modifications to the Covenant Described Above

Any additional covenants and/or modifications to the covenants described above with respect to any series of debt securities, including any covenants relating to limitations on incurrence of indebtedness or other financial covenants, will be set forth in the applicable indenture or supplemental indenture and described in the applicable prospectus supplement relating to that series of debt securities.

Unless the applicable prospectus supplement indicates otherwise, the subordinated debt indenture does not contain any other provision which restricts us from, among other things:

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Events of Default, Waiver and Notice

Events of Default

The events of default with respect to any series of debt securities issued under it, subject to any modifications or deletions provided in any supplemental indenture with respect to any specific series of debt securities, include the following events:

If an event of default under any indenture with respect to debt securities of any series at the time outstanding occurs and is continuing, then in every case other than in the case of specific events of bankruptcy, insolvency or reorganization, or court appointment of a receiver, liquidator or trustee of us or any significant subsidiary or either of our property, in which case acceleration will be automatic, the applicable trustee or the holders of not less than 25% of the principal amount of the outstanding debt securities of that series will have the right to declare the principal amount, or, if the debt securities of that series are original issue discount securities or indexed securities, the portion of the principal amount as may be specified in the terms of that series, of all the debt securities of that series to be due and payable immediately by written notice to us, and to the applicable trustee if given by the holders. At any time after a declaration of acceleration has been made with respect to debt securities of a series, or of all debt securities then outstanding under any indenture, as the case may be, but before a judgment or decree for payment of the money due has been obtained by the applicable trustee, however, the holders of not less than a majority in principal amount of the outstanding debt securities of that series, or of all debt securities then outstanding under the applicable indenture, as the case may be, may annul the declaration of acceleration and waive any default in respect of those debt securities if:

Waiver

Each indenture also will provide that the holders of not less than a majority in principal amount of the outstanding debt securities of any series, or of all debt securities then outstanding under the applicable indenture, as the case may be, may waive any past default with respect to that series and its consequences, except a default:

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Notice

Each trustee will be required to give notice to the holders of the applicable debt securities within 90 days of a default under the applicable indenture unless the default has been cured or waived; but the trustee may withhold notice of any default, except a default in the payment of the principal of, or premium, if any, or interest on the debt securities or in the payment of any sinking fund installment in respect of the debt securities, if specified responsible officers of the trustee consider the withholding to be in the interest of the holders.

The holders of debt securities of any series may not institute any proceedings, judicial or otherwise, with respect to the indentures or for any remedy under the indentures, except in the case of failure of the applicable trustee, for 60 days, to act after the trustee has received a written request to institute proceedings in respect of an event of default from the holders of not less than 25% in principal amount of the outstanding debt securities of that series, as well as an offer of indemnity reasonably satisfactory to the trustee, and provided that no direction inconsistent with such written request has been given to the trustee during such 60-day period by the holders of a majority of the outstanding debt securities of that series. However, any holder of debt securities is not prohibited from instituting suit for the enforcement of payment of the principal of, and premium, if any, and interest on the debt securities at their respective due dates.

Subject to the trustee’s duties in case of default, no trustee will be under any obligation to exercise any of its rights or powers under an indenture at the request or direction of any holders of any series of debt securities then outstanding under that indenture, unless the holders offer to the trustee reasonable security or indemnity. Subject to such provisions for the indemnification of the trustee, the holders of not less than a majority in principal amount of the outstanding debt securities of any series, or of all debt securities then outstanding under an indenture, as the case may be, will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the applicable trustee, or of exercising any trust or power conferred upon the trustee. A trustee may refuse, however, to follow any direction that is in conflict with any law or the applicable indenture that may involve the trustee in personal liability or may be unduly prejudicial to the holders of debt securities of that series not joining in the direction.

Within 180 days after the end of each fiscal year, we will be required to deliver to each trustee a certificate, signed by one of several specified officers, stating whether or not that officer has knowledge of any default under the applicable indenture and, if so, specifying each default and the nature and status of the default.

Modification of the Indentures

Except as otherwise specifically provided in the applicable indenture, with the consent of the holders of not less than a majority in principal amount of all outstanding debt securities issued under that indenture that are affected by the modification or amendment, we may enter into supplemental indentures with the trustee for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of such indenture or of modifying in any manner the rights of the holders under debt securities issued under such indenture. However, no modification or amendment may, without the consent of the holder of each debt security affected by the modification or amendment:

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The holders of not less than a majority in principal amount of the outstanding debt securities of each series affected by the modification or amendment will have the right to waive compliance by us with specific covenants in the indenture.

We and the respective trustee may modify and amend an indenture without the consent of any holder of debt securities for any of the following purposes:

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In determining whether the holders of the requisite principal amount of outstanding debt securities of a series have given any request, demand, authorization, direction, notice, consent or waiver under the indenture or whether a quorum is present at a meeting of holders of debt securities:

Discharge, Defeasance and Covenant Defeasance

Discharge

We may be permitted under the applicable indenture to discharge specific obligations to holders of any series of debt securities (1) that have not already been delivered to the applicable trustee for cancellation and (2) that either have become due and payable or will, within one year, become due and payable or scheduled for redemption, by irrevocably depositing with the applicable trustee, in trust, money or funds certified to be sufficient to pay when due, whether at maturity, upon redemption or otherwise, the principal of, and premium, if any, on and interest on the debt securities.

Defeasance and Covenant Defeasance

If the provisions of the applicable indenture relating to defeasance and covenant defeasance are made applicable to the debt securities of or within any series, we may elect either:

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in either case upon the irrevocable deposit by us with the applicable trustee, in trust, of an amount, in currency or currencies or government obligations, or both, sufficient without reinvestment to make scheduled payments of the principal of, and premium, if any, and interest on the debt securities, when due, whether at maturity, upon redemption or otherwise, and any mandatory sinking fund or analogous payments.

A trust will only be permitted to be established if, among other things:

In general, if we elect covenant defeasance with respect to any debt securities and payments on those debt securities are declared due and payable because of the occurrence of an event of default, the amount of money and/or government obligations on deposit with the applicable trustee would be sufficient to pay amounts due on those debt securities at the time of their stated maturity, but may not be sufficient to pay amounts due on those debt securities at the time of the acceleration resulting from the event of default. In that case, we would remain liable to make payment of the amounts due on the debt securities at the time of acceleration.

The applicable prospectus supplement may further describe the provisions, if any, permitting defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the debt securities of or within a particular series

Regarding the Trustees

We will designate the trustee under the senior and subordinated debt indentures in the applicable prospectus supplement. From time to time, we may enter into banking or other relationships with any of such trustees or their affiliates.

There may be more than one trustee under each indenture, each with respect to one or more series of debt securities. Any trustee may resign or be removed with respect to one or more series of debt securities, and a successor trustee may be appointed to act with respect to such series.

If two or more persons are acting as trustee with respect to different series of debt securities, each trustee will be a trustee of a trust under the indenture separate from the trust administered by any other such trustee.

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Except as otherwise indicated in this prospectus, any action to be taken by the trustee may be taken by each such trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the indenture.

Governing Law

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

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DESCRIPTION OF COMMON STOCK

The following description is a general summary of the terms of our common stock. The description below does not purport to be complete and is subject to and qualified in its entirety by reference to our certificate of incorporation and bylaws. The description herein does not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of our certificate of incorporation and bylaws because they, and not the summary, define the rights of holders of shares of our common stock. You can obtain copies of our certificate of incorporation and bylaws by following the directions under the heading “Where You Can Find More Information.”

General

Our certificate of incorporation provides the authority to issue 200,000,000 shares of common stock, par value $0.0001 per share. At May 1, 2015, there were 89,191,733 shares of common stock issued and outstanding and we had outstanding stock options granted to directors, officers and other employees for 147,455 shares of our common stock.

Each share of our common stock has the same relative rights and is identical in all respects to each other share of our common stock. Our common stock is non-withdrawable capital, is not of an insurable type and is not insured by the Federal Deposit Insurance Corporation or any other governmental entity.

Voting Rights

Holders of our common stock are entitled to one vote per share on each matter properly submitted to stockholders for their vote, including the election of directors. Holders of our common stock do not have the right to cumulate their votes for the election of directors, which means that the holders of more than 50% of the shares of common stock voting for the election of directors can elect 100% of the directors standing for election at any meeting if they choose to do so. In that event, the holders of the remaining shares voting for the election of directors will not be able to elect any person or persons to our board of directors at that meeting. Generally, in matters other than the election of directors and business combinations and other extraordinary transactions, the affirmative vote of the majority of shares present and entitled to vote on the subject matter constitutes the act of the stockholders. A nominee to our board of directors will be elected, in uncontested elections (as defined in our bylaws), if the votes cast for such nominee’s election exceed the votes cast against such nominee’s election. In all director elections other than uncontested elections, the vote standard will continue to be a plurality of votes cast, and stockholders shall not be permitted to vote against any nominee for director.

Liquidation Rights

The holders of our common stock and the holders of any class or series of stock entitled to participate with the holders of our common stock as to the distribution of assets in the event of any liquidation, dissolution or winding-up of us, whether voluntary or involuntary, will become entitled to participate equally in the distribution of any of our assets remaining after we have paid, or provided for the payment of, all of our debts and liabilities and after we have paid, or set aside for payment, to the holders of any class of stock having preference over the common stock in the event of liquidation, dissolution or winding-up, the full preferential amounts, if any, to which they are entitled.

Dividends

The holders of our common stock and any class or series of stock entitled to participate with the holders of our common stock are entitled to receive dividends declared by our board of directors out of any assets legally available for distribution. The board may declare dividends out of surplus, or if no surplus exists, out of net profits for the fiscal year in which the dividend is declared and/or the preceding fiscal year, only if the amount of

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capital is greater than or equal to the aggregate amount of the capital represented by the issued and outstanding stock of all classes having a preference upon the distribution of assets. The terms and conditions of other securities we issue may restrict our ability to pay dividends to holders of our common stock. In addition, as a holding company, our main source of funds to pay dividends is distributions from our subsidiaries and, therefore, our ability to pay distributions is affected by the ability of our subsidiaries to pay dividends. The ability of our bank subsidiary, and our ability, to pay dividends in the future is, and could in the future be further, influenced by bank regulatory requirements and capital guidelines.

Miscellaneous

The holders of our common stock have no preemptive or conversion rights for any shares that may be issued. Our common stock is not subject to additional calls or assessments, and all shares of our common stock currently outstanding are fully paid and non-assessable.

Anti-Takeover Effects of Provisions of our Certificate of Incorporation and Bylaws and Delaware Law

Some provisions of Delaware law and our certificate of incorporation and bylaws contain provisions that could make it more difficult to (1) acquire us by means of a tender offer, proxy contest or otherwise or (2) remove our incumbent officers and directors. These provisions, summarized below, are intended to encourage persons seeking to acquire control of us to first negotiate with our board of directors. These provisions also serve to discourage hostile takeover practices and inadequate takeover bids.

Undesignated Preferred Stock

Our board of directors has the ability to authorize undesignated preferred stock, which allows the board of directors to issue preferred stock with voting or other rights or preferences that could impede the success of any unsolicited attempt to change control of our company. This ability may have the effect of deferring hostile takeovers or delaying changes in control or management of our company.

Special Stockholders’ Meetings and Advanced Notice Requirements for Stockholder Proposals

Our certificate of incorporation and bylaws provide that a special meeting of stockholders may be called only by our board of directors, the chairman of the board, or by our chief executive officer or president. In addition, our bylaws require advance notice procedures for stockholder proposals to be brought before an annual meeting of the stockholders, including the nomination of directors. Stockholders at an annual meeting may only consider the proposals specified in the notice of meeting or brought before the meeting by or at the direction of the board, or by a stockholder of record on the record date for the meeting who (1) is entitled to vote at the meeting, (2) has delivered a timely written notice in proper form to our secretary of the stockholder’s intention to bring such business before the meeting, (3) attends (or has a qualified representative attend) the stockholder meeting and (4) has otherwise complied with the provisions of our Bylaws and applicable law. These provisions could have the effect of delaying any stockholder actions until the next stockholder meeting, even if they are favored by the holders of a majority of our outstanding voting stock.

No Action by Written Consent

Our certificate of incorporation and bylaws do not permit stockholders to act by written consent in lieu of a meeting.

Election and Removal of Directors

Our certificate of incorporation provides for the division of our board of directors into three classes of directors, each class as nearly as equal as possible, with each serving staggered, three-year terms. Once elected,

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directors may be removed only for cause by the holders of a majority of shares then entitled to vote in an election of directors. In addition, our certificate of incorporation and bylaws provide that any vacancies on the board of directors may be filled only by a majority of the remaining directors. This system of electing and removing directors and filling vacancies may tend to discourage a third party from making a tender offer or otherwise attempting to obtain control of us because it generally makes it more difficult for stockholders to replace a majority of the directors.

Amendment of Certain Provisions of our Organizational Documents

Any amendment to our certificate of incorporation must be approved by our board of directors and a majority of the outstanding shares of each class of shares entitled to vote thereon at a duly called annual or special meeting; provided, that in addition to any vote of any class of shares required by law or the certificate of incorporation, the affirmative vote of holders of at least a majority of the voting power of all of the then outstanding shares of our capital stock entitled to vote generally in the election of directors, voting together as a single class, is required to amend certain of the provisions contained in the certificate of incorporation regarding stockholder actions, classification of directors, removal of directors, filling of director vacancies, bylaw amendments, limitation of liability of directors, the exclusive forum for certain litigation, and amendments to the certificate of incorporation. Our bylaws may be amended by the affirmative vote of a majority of the directors present at a meeting at which a quorum is present or by the affirmative vote of the holders of at least 66-2/3% of the voting power of all of the shares of capital stock issued and outstanding and entitled to vote in any election of directors, voting as a single class.

Business Combinations

We have not opted out of Section 203 of the Delaware General Corporation Law, an anti-takeover law, and are therefore subject to its provisions. In general, Section 203 prohibits a publicly held Delaware corporation from engaging in a business combination, such as a merger, with a person or group owning 15% or more of the corporation’s outstanding voting stock, referred to as an “interested stockholder” under Section 203, for a period of three years following the date the person became an interested stockholder, unless (with certain exceptions) the business combination or the transaction in which the person became an interested stockholder is approved in a prescribed manner.

These and other provisions of Delaware law and our certificate of incorporation and bylaws could have the effect of discouraging others from attempting hostile takeovers and, as a consequence, they may also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. Such provisions may also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions which shareholders may otherwise deem to be in their best interests.

Since the terms of our certificate of incorporation and bylaws may differ from the general information we are providing, you should only rely on the actual provisions of our certificate of incorporation and bylaws. If you would like to read our certificate of incorporation and bylaws, you may request a copy from us by following the directions under the heading “Where You Can Find More Information.”

NYSE Listing

Our common stock is listed on the New York Stock Exchange under the symbol “WAL.”

DESCRIPTION OF PREFERRED STOCK

The following description is a general summary of the terms of the preferred stock which we may issue. The description below and in any prospectus supplement does not purport to be complete and is subject to and qualified in its entirety by reference to our certificate of incorporation, and the applicable certificate of designation to our certificate of incorporation, determining the terms of the related series of preferred stock and our bylaws, each of which we will make available upon request. The descriptions herein and in the applicable prospectus supplement do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of our certificate of incorporation, the applicable certificate of designation and our bylaws because they, and not the summaries, define your rights as holders of shares of our preferred stock.

General

We are authorized to issue 20,000,000 shares of preferred stock, par value $0.0001 per share. As of May 1, 2015, 70,500 shares of preferred stock were issued and outstanding, consisting of 70,500 shares of Non-Cumulative Perpetual Preferred Stock, Series B. Our certificate of incorporation, subject to limitations prescribed in such certificate and subject to limitations prescribed by Delaware law, authorizes the board of directors, from time to time by resolution and without further stockholder action, to provide for the issuance of shares of preferred stock, in one or more series, and to fix the designation, powers, preferences and other rights of the shares and to fix the qualifications, limitations and restrictions thereof. As a result of its broad discretion with respect to the creation and issuance of preferred stock without stockholder approval, the board of directors could adversely affect the voting power of the holders of common stock and, by issuing shares of preferred stock with certain voting, conversion and/or redemption rights, could discourage any attempt to obtain control of us.

Terms of the Preferred Stock That We May Offer and Sell to You

You should refer to the prospectus supplement relating to the class or series of preferred stock for the specific terms of that class or series, including:

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Ranking

Unless otherwise specified in the applicable prospectus supplement, the preferred stock will, with respect to distribution rights and rights upon liquidation, dissolution or winding up of our affairs, rank:

For purposes of this subheading, the term “equity securities” does not include convertible debt securities.

Distributions

Holders of the preferred stock of each series will be entitled to receive, when, as and if declared by our board of directors, out of our assets legally available for payment to stockholders, cash distributions, or distributions in kind or in other property if expressly permitted and described in the applicable prospectus supplement, at the rates and on the dates as we will set forth in the applicable prospectus supplement. We will pay each distribution to holders of record as they appear on our stock transfer books on the record dates determined by our board of directors.

Distributions on any class or series of preferred stock, if cumulative, will be cumulative from and after the date set forth in the applicable prospectus supplement. If our board of directors fails to declare a distribution payable on a distribution payment date on any class or series of preferred stock for which distributions are non-cumulative, then the holders of that class or series of preferred stock will have no right to receive a distribution in respect of the distribution period ending on that distribution payment date, and we will have no obligation to pay the distribution accumulated for that period, whether or not distributions on that series are declared payable on any future distribution payment date.

If any shares of the preferred stock of any class or series are outstanding, no full dividends will be declared or paid or set apart for payment on our preferred stock of any other class or series ranking, as to dividends, equally with or junior to the preferred stock of the class or series for any period unless all required dividends are paid. The phrase “all required dividends are paid” when used in this prospectus with respect to class or series of preferred stock means that:

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When dividends are not paid in full, or a sum sufficient for the full payment is not so set apart, upon the shares of preferred stock of any class or series and the shares of any other class or series of preferred stock ranking equally as to dividends with the preferred stock of the class or series, all dividends declared upon shares of preferred stock of the class or series and any other class or series of preferred stock ranking equally as to dividends with the preferred stock will be declared equally so that the amount of dividends declared per share on the preferred stock of the class or series and the other class or series of preferred stock will in all cases bear to each other the same ratio that accrued and unpaid dividends per share on the shares of preferred stock of the class or series, which will not include any accumulation in respect of unpaid dividends for prior dividend periods if the preferred stock does not have cumulative dividend, and the other class or series of preferred stock bear to each other. No interest, sum of money in lieu of interest, will be payable in respect of any dividend payment or payments on preferred stock of the class or series which may be in arrears.

Except as provided in the immediately preceding paragraph, unless all required dividends are paid, no dividends, other than in common stock or other stock ranking junior to the preferred stock of the class or series as to dividends and upon liquidation, dissolution or winding-up of us, will be declared or paid or set aside for payment or other distribution will be declared or made upon the common stock or any of our other stock ranking junior or equally with the preferred stock of the class or series as to dividends or upon liquidation, nor will any common stock or any of our other capital stock ranking junior to or equally with preferred stock of the class or series as to dividends or upon liquidation, dissolution or winding-up of us be redeemed, purchased or otherwise acquired for any consideration, or any moneys be paid to or made available for a sinking fund for the redemption of any shares of any stock, by us except by conversion into or exchange for our other stock ranking junior to the preferred stock of the class or series as to dividends and upon liquidation, dissolution or winding-up of us.

Any dividend payment made on shares of a class or series of preferred stock will first be credited against the earliest accrued but unpaid dividend due with respect to shares of the class or series which remains payable.

Redemption

If so provided in the applicable prospectus supplement, the preferred stock will be subject to mandatory redemption or redemption at our option, in whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

Liquidation Preference

Upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, then, before any distribution or payment will be made to the holders of any common stock or any other class or series of shares of our capital stock ranking junior to the preferred stock in the distribution of assets upon any liquidation, dissolution or winding up of our affairs, the holders of each series or class of preferred stock will be entitled to receive out of our assets legally available for distribution to stockholders liquidating distributions in the amount of the liquidation preference set forth in the applicable prospectus supplement, plus an amount equal to all accumulated and unpaid distributions. If, upon the voluntary or involuntary liquidation, dissolution or winding up, our available assets are insufficient to pay the amount of the liquidating distributions on all outstanding shares of preferred stock and the corresponding amounts payable on all shares of other classes or series of shares of our capital stock ranking equally with the preferred stock in the distribution of assets, then the holders of the preferred stock and all other classes or series of shares of capital stock will share ratably in any distribution of assets in proportion to the full liquidating distributions to which they would otherwise be respectively entitled.

If liquidating distributions will have been made in full to all holders of preferred stock, our remaining assets will be distributed among the holders of any other classes or series of shares of capital stock ranking junior to the preferred stock upon liquidation, dissolution or winding up, according to their respective rights and preferences and in each case according to their respective number of shares.

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For those purposes, the consolidation or merger of us with or into any other corporation, trust or entity, or the sale, lease or conveyance of all or substantially all of our property or business, will not be deemed to constitute a liquidation, dissolution or winding up of our affairs.

Voting Rights

Holders of preferred stock will not have any voting rights, except as set forth below or as otherwise from time to time required by law, or as otherwise provided in the certificate of designation or the resolutions establishing such series and as indicated in the applicable prospectus supplement.

Under the Delaware General Corporation Law, holders of outstanding shares of a series of preferred stock may be entitled to vote as a separate class on a proposed amendment to the terms of that series of preferred stock or our certificate of incorporation, if the amendment would:

Conversion Rights

The terms and conditions, if any, upon which any class or series of preferred stock are convertible into or exchangeable for our other securities or rights or those of other issuers, including, without limitation, common stock, debt securities, trust preferred securities or another series of preferred stock, or any combination of the foregoing, will be set forth in the applicable prospectus supplement relating to the preferred stock. The terms will include the name of the issuer of the other securities or rights and the number or principal amount of the securities or rights into which the shares of preferred stock are convertible or exchangeable, the conversion or exchange price or rate or the manner of calculating the price, the conversion or exchange date(s) or period(s), provisions as to whether conversion or exchange will be at the option of the holders of the preferred stock or at our or other issuer’s option, the events requiring an adjustment of the conversion or exchange price or rate and provisions affecting conversion or exchange in the event of the redemption of the series of preferred stock.

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DESCRIPTION OF DEPOSITARY SHARES

The following description, together with the applicable prospectus supplements, summarizes certain terms and provisions of the depositary shares that we may offer under this prospectus and the related deposit agreements and depositary receipts. The following summary relates to terms and conditions applicable to these types of securities generally. The particular terms of any series of depositary shares will be those set forth in the applicable deposit agreement and summarized in the applicable prospectus supplement. If indicated in the applicable prospectus supplement, the terms of any series may differ from the terms summarized below.

Specific deposit agreements and depositary receipts will contain additional important terms and provisions and will be incorporated by reference into the registration statement which includes this prospectus before we issue any depositary shares. The descriptions herein and in the applicable prospectus supplement do not restate those agreements and receipts in their entirety and do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the applicable deposit agreement and deposit certificate because they, and not the summaries, define your rights as holders of the depositary shares. For more information, please review the forms of these documents, which will be filed with the SEC will be available as described under the heading “Where You Can Find More Information” above.

General

We may elect to offer fractional shares of preferred stock rather than full shares of preferred stock. If so, we will issue “depositary receipts” for these “depositary shares.” Each depositary share will represent a fraction of a share of a particular series of preferred stock. Each holder of a depositary share will be entitled, in proportion to the fraction of preferred stock represented by that depositary share, to the rights and preferences of the preferred stock, including dividend, voting, redemption, conversion and liquidation rights, if any. We will enter into a deposit agreement with a depositary, which will be named in the applicable prospectus supplement.

In order to issue depositary shares, we will issue preferred stock and immediately deposit these shares with the depositary. The depositary will then issue and deliver depositary receipts to the persons who purchase depositary shares. Each whole depositary share issued by the depositary may represent a fraction of a share held by the depositary. The depositary will issue depositary receipts in a form that reflects whole depositary shares, and each depositary receipt may evidence any number of whole depositary shares.

Pending the preparation of definitive engraved depositary receipts, a depositary may, upon our written order, issue temporary depositary receipts, which will temporarily entitle the holders to all the rights pertaining to the definitive depositary receipts. We will bear the costs and expenses of promptly preparing definitive depositary receipts and of exchanging the temporary depositary receipts for definitive depositary receipts.

Dividends and Other Distributions

The depositary will distribute all cash and non-cash dividends and distributions it receives with respect to the underlying preferred stock to the record holders of depositary shares in proportion to the number of depositary shares they hold. In the case of non-cash distributions, the depositary may determine that it is not feasible to make the distribution. If so, the depositary may, with our approval, sell the property and distribute the net proceeds from the sale to the holders. The amounts distributed by the depositary will be reduced by any amount required to be withheld by us or the depositary on account of taxes.

Redemption of Depositary Shares

If we redeem the series of preferred stock that underlies the depositary shares, the depositary will redeem the depositary shares from the proceeds it receives from the redemption of the preferred stock it holds. The depositary will redeem the number of depositary shares that represent the amount of underlying preferred stock

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that we have redeemed. The redemption price for depositary shares will be in proportion to the redemption price per share that we paid for the underlying preferred stock. If we redeem less than all of the depositary shares, the depositary will select which depositary shares to redeem by lot, or some substantially equivalent method.

After a redemption date is fixed, the depositary shares to be redeemed no longer will be considered outstanding. The rights of the holders of the depositary shares will cease, except for the rights to receive money or other property upon redemption. In order to redeem their depositary shares, holders will surrender their depositary receipts to the depositary.

Voting the Preferred Stock

We will notify the depositary about any meeting at which the holders of preferred stock are entitled to vote, and the depositary will mail the information to the record holders of depositary shares related to that preferred stock. Each record holder of depositary shares on the record date will be entitled to instruct the depositary on how to vote the shares of preferred stock represented by that holder’s depositary shares. The depositary will vote the preferred stock represented by the depositary shares in accordance with these instructions, provided the depositary receives these instructions sufficiently in advance of the meeting. If the depositary does not receive instructions from the holders of the depositary shares, the depositary will abstain from voting the preferred stock that underlies those depositary shares.

Withdrawal of Preferred Stock

When a holder surrenders depositary receipts at the corporate trust office of the depositary, and pays any necessary taxes, charges or other fees, the holder will be entitled to receive the number of whole shares of the related series of preferred stock, and any money or other property, if any, represented by the holder’s depositary shares. Once a holder exchanges depositary shares for whole shares of preferred stock, that holder cannot “re-deposit” these shares of preferred stock with the depositary, or exchange them for depositary shares. If a holder delivers depositary receipts that represent a number of depositary shares that exceeds the number of whole shares of related preferred stock the holder seeks to withdraw, the depositary will issue a new depositary receipt to the holder that evidences the excess number of depositary shares.

Amendment and Termination of the Deposit Agreement

We and the depositary can agree, at any time, to amend the form of depositary receipt and any provisions of the depositary receipt and any provisions of the deposit agreement. However, if an amendment has a material adverse effect on the rights of the holders of related depositary shares, the holders of at least a majority of the depositary shares then outstanding must first approve the amendment. Every holder of a depositary receipt at the time an amendment becomes effective will be bound by the amended deposit agreement. However, subject to any conditions in the deposit agreement or applicable law, no amendment can impair the right of any holder of a depositary share to receive shares of the related preferred stock, or any money or other property represented by the depositary shares, when they surrender their depositary receipts.

We can terminate the deposit agreement at any time, as long as the depositary mails notice of termination to the record holders of depositary shares then outstanding at least 30 days prior to the date fixed for termination. Upon termination, the depositary shall deliver to each holder of depositary receipts, upon surrender of the depositary receipts held by such holder, such number of whole or fractional shares of preferred stock as are represented by the depositary shares evidenced by such depositary receipts, together with any other property held by the depositary with respect to such depositary receipt.

Charges of Depositary

We will pay all transfer and other taxes and the government charges that relate solely to the depositary arrangements. We will also pay the charges of each depositary, including charges in connection with the initial deposit of the related series of preferred stock, the initial issuance of the depositary shares, and all withdrawals of

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shares of the related series of preferred stock. However, holders of depositary receipts will pay the fees and expenses of the depositary for any duties requested by such holders to be performed which are outside of those expressly provided for in the deposit agreement.

Resignation and Removal of Depositary

The depositary may resign at any time by delivering written notice of its decision to us. We may remove the depositary at any time. Any resignation or removal will take effect when we appoint a successor depositary. We must appoint the successor depositary within a specified time after delivery of the notice of resignation or removal. The successor depositary shall be a bank or trust company that has its principal office in the United States and has a combined capital and surplus of at least $50,000,000.

Miscellaneous

We will be required to furnish certain information to the holders of the preferred stock underlying any depositary shares. The depositary, as the holder of the underlying preferred stock, will forward any report or information it receives from us to the holders of depositary shares.

Neither we nor the depositary will be liable if its ability to perform its obligations under the deposit agreement is prevented or delayed by law or any circumstance beyond its control. Both we and the depositary will be obligated to use our best judgment and to act in good faith in performing our respective duties under the deposit agreement. We and the depositary will be liable only for gross negligence and willful misconduct in performing our respective duties under the deposit agreement. Neither we nor the depositary will be obligated to appear in, prosecute or defend any legal proceeding with respect to any depositary receipts, depositary shares or preferred stock unless we or the depositary receive what we, in our sole discretion, determine to be a satisfactory indemnity from one or more holders of the depositary shares. We and the depositary will evaluate any proposed indemnity in order to determine whether the financial protection afforded by the indemnity is sufficient to reduce each party’s risk to a satisfactory and customary level. We and the depositary may rely on the advice of legal counsel or accountants of the choice of each. We and the depositary may also rely on information provided by persons we and they believe, in good faith, to be competent, and on documents we and they believe, in good faith, to be genuine.

The applicable prospectus supplement will identify the depositary’s corporate trust office. Unless the prospectus supplement indicates otherwise, the depositary will act as transfer agent and registrar for depositary receipts, and if we redeem shares of preferred stock, the depositary will act as redemption agent for the corresponding depositary receipts.

Title

We, each depositary and any agent of ours or the applicable depositary may treat the registered owner of any depositary share as the absolute owner of the depositary shares for all purposes, including making payment, regardless of whether any payment in respect of the depositary share is overdue and regardless of any notice to the contrary.

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DESCRIPTION OF WARRANTS

General

We may issue warrants to purchase our debt securities, common stock or preferred stock or units of two or more of these types of securities, which are collectively referred to in this prospectus as “underlying warrant securities.” We may issue warrants independently or together with any underlying warrant securities and such warrants may be attached to or separate from those underlying warrant securities. We will issue the warrants under warrant agreements to be entered into between us and a bank or trust company, as warrant agent, as more fully described in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

The applicable prospectus supplement will contain a description of the following terms:

Exercise of Warrants

Each warrant will entitle its holder to purchase, for cash and/or securities (as will be specified in the applicable prospectus supplement), the amount or number of debt securities, shares of preferred stock, or shares of common stock, at the exercise price, as will in each case be set forth in, or be determinable as set forth in, the

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applicable prospectus supplement. Holders may exercise warrants at any time up to the close of business on the expiration date set forth in the applicable prospectus supplement relating to the warrants offered thereby. After the close of business on the expiration date, unexercised warrants will become void.

Holders of warrants may exercise their respective warrants in the manner set forth in the applicable prospectus supplement relating to such warrants. Upon receipt of payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the prospectus supplement, we will, as soon as practicable, forward the underlying warrant securities purchasable upon exercise of the warrants. If a holder exercises less than all of the warrants represented by the warrant certificate, the warrant agent will issue a new warrant certificate for the remaining warrants.

Prior to the exercise of any warrants to purchase debt securities or other securities, including shares of preferred stock or common stock, holders of the warrants will not have any of the rights of holders of the debt securities or other securities, including shares of preferred stock or common stock purchasable upon exercise, including:

The descriptions of the warrant agreements in this prospectus and in any prospectus supplement are summaries of certain material provisions of the applicable warrant agreements. These descriptions do not restate those agreements in their entirety and do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the applicable warrant agreement and warrant certificate relating to the warrants because they, and not the summaries, define your rights as holders of the warrants or any warrant units. For more information, please review the forms of these documents, which will be filed with the SEC and will be available as described under the heading “Where You Can Find More Information” above.

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DESCRIPTION OF PURCHASE CONTRACTS

As may be specified in a prospectus supplement, we may issue purchase contracts obligating holders to purchase from us, and obligating us to sell to the holders, a number of debt securities, shares of our common stock, preferred stock or depositary shares or warrants, at a future date or dates. The price per purchase contract security may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula set forth in the purchase contracts. Under the purchase contracts, we may be required to make periodic payments to the holders of the units or vice versa. These payments may be unsecured or prefunded on some basis to be specified in the applicable prospectus supplement.

The purchase contracts may require holders to secure their obligations under the contracts in a specified manner and, in specified circumstances, we may deliver newly issued prepaid purchase contracts, or prepaid securities, when we transfer to a holder any collateral securing the holder’s obligations under the original purchase contract.

The purchase contracts may be issued separately or as part of units consisting of a purchase contract and one or more other securities, which may include our debt securities, depositary shares, preferred securities, common stock, warrants or debt obligations or government securities, and which may secure the holder’s obligations to purchase the purchase contract security under the purchase contract.

The applicable prospectus supplement relating to any purchase contracts we are offering will specify the material terms of the purchase contracts, whether they will be issued separately or as part of units, and any applicable pledge or depository arrangements.

The descriptions of the purchase contracts and any applicable underlying security or pledge or depository arrangements in this prospectus and in any prospectus supplement are summaries of certain material provisions of the applicable agreements. These descriptions do not restate those agreements in their entirety and do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the applicable agreements because they, and not the summaries, define your rights as holders of the purchase contracts. We will make copies of the relevant agreements available as described under the heading “Where You Can Find More Information” above.

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DESCRIPTION OF UNITS

As specified in the applicable prospectus supplement, we may issue units comprised of one or more of the other securities described in this prospectus in any combination. Each unit may also include debt obligations of third parties, such as U.S. Treasury securities. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The prospectus supplement will describe:

The descriptions of the units and any applicable underlying security or pledge or depository arrangements in this prospectus and in any prospectus supplement are summaries of the material provisions of the applicable agreements. These descriptions do not restate those agreements in their entirety and do not contain all of the information that you may find useful or that may be important to you. You should refer to the provisions of the applicable agreements because they, and not the summaries, define your rights as holders of the units. We will make copies of the relevant agreements available as described under the heading “Where You Can Find More Information” above.

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