Filed Pursuant to Rule 424(b)(2)
Registration Statement Nos. 333-132747 to 333-132747-10

PROSPECTUS

[UBS AG LOGO]

UBS Preferred Funding Trust V

UBS Preferred Funding Trust VI

UBS Preferred Funding Trust VII

UBS Preferred Funding Trust VIII

UBS Preferred Funding Trust IX

Noncumulative Trust Preferred Securities

representing a corresponding amount of

Noncumulative Company Preferred Securities

of

UBS Preferred Funding Company LLC V

UBS Preferred Funding Company LLC VI

UBS Preferred Funding Company LLC VII

UBS Preferred Funding Company LLC VIII

UBS Preferred Funding Company LLC IX

guaranteed on a subordinated basis by

UBS AG

UBS Preferred Funding Trust V, UBS Preferred Funding Trust VI, UBS Preferred Funding Trust VII, UBS Preferred Funding Trust VIII and UBS Preferred Funding Trust IX (each, a “UBS Preferred Funding Trust” and together, the “UBS Preferred Funding Trusts”) from time to time may severally offer to sell trust preferred securities representing a corresponding amount of related company preferred securities and related rights under subordinated guarantees by UBS AG.

(continued on next page)

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The trust preferred securities will not be deposit liabilities of UBS AG and will not be insured by the United States Federal Deposit Insurance Corporation or any other governmental agency of the United States, Switzerland or any other jurisdiction.

UBS AG may offer and sell the trust preferred securities to or through one or more underwriters, dealers and agents, including the firms named below, or directly to purchasers, on a delayed or continued basis.

This prospectus may be used in the initial sale of the trust preferred securities. In addition, UBS AG, UBS Securities LLC, UBS Financial Services Inc. or any other affiliate controlled by UBS AG may use this prospectus in a market-making transaction involving the trust preferred securities after the initial sale. These transactions may be executed at negotiated prices that are related to market prices at the time of purchase or sale, or at other prices. UBS AG and its affiliates may act as principal or agent in these transactions. Unless UBS AG or its agent informs you otherwise in the confirmation of sale, this prospectus is being used in a market making transaction.

UBS Investment Bank UBS Financial Services Inc.

The date of this Prospectus is March 27, 2006

(continued from previous page)

UBS Preferred Funding Company LLC V, UBS Preferred Funding Company LLC VI, UBS Preferred Funding Company LLC VII, UBS Preferred Funding Company LLC VIII and UBS Preferred Funding Company LLC IX (each, a “UBS Preferred Funding Company” and together, the “UBS Preferred Funding Companies”) will issue company preferred securities. Any company preferred securities which may be issued by a UBS Preferred Funding Company will provide holders with rights to distributions and redemption and liquidation payments that are similar to those of the most senior ranking noncumulative perpetual preferred shares issued directly by UBS AG that have financial terms equivalent to those of such company preferred securities.

Each UBS Preferred Funding Trust will use the proceeds from the sale of its trust preferred securities to purchase company preferred securities (the “related company preferred securities”) from a UBS Preferred Funding Company (the “related UBS Preferred Funding Company”). The related UBS Preferred Funding Company will use the proceeds from the sale of the related company preferred securities to the UBS Preferred Funding Trust (the “related UBS Preferred Funding Trust”) and from the sale of company common securities to UBS AG to acquire subordinated notes (the “related subordinated notes”) issued by the Cayman Islands branch of UBS AG. The trust preferred securities, the related company preferred securities and the related subordinated notes that will be issued in any particular offering will have corresponding terms. Dividends and redemption and liquidation payments paid by the related UBS Preferred Funding Company on the related company preferred securities will pass through the related UBS Preferred Funding Trust to you as distributions and redemption and liquidation payments on your trust preferred securities.

UBS AG will guarantee, on a subordinated basis, dividend, redemption and liquidation payment obligations under any company preferred securities.

This prospectus describes the general terms that may apply to any trust preferred securities and the corresponding company preferred securities and the general manner in which trust preferred securities may be offered. The specific terms of any trust preferred securities to be offered, and the specific manner in which they may be offered and the terms of any related company preferred securities, may be different from those described in this prospectus and will be described in the applicable supplement to this prospectus.

TABLE OF CONTENTS

Introduction	1
Cautionary Note Regarding Forward-Looking Statements	2
Incorporation of Information About UBS AG	4
Where You Can Find More Information	5
Presentation of Financial Information	6
Limitations on Enforcement of U.S. Laws Against UBS AG, Its Management and Others	7
Capitalization of UBS	7
UBS	8
The UBS Preferred Funding Trusts	10
The UBS Preferred Funding Companies	11
Use of Proceeds	17
Description of Trust Preferred Securities	18
Description of Company Preferred Securities	25
Book-Entry Issuance of Trust Preferred Securities	39
Description of UBS AG Subordinated Guarantees	44
Description of Subordinated Notes of UBS AG	49
U.S. Tax Considerations	52
Tax Considerations Under the Laws of Switzerland	59
ERISA Considerations	61
Plan of Distribution	63
Validity of the Securities	63
Experts	63

CERTAIN TERMS

In this prospectus:

• when we refer to “UBS AG,” we mean UBS AG on a parent only basis.

• when we refer to “UBS” or “UBS Group,” we mean UBS AG and its consolidated subsidiaries.

• when we refer to “USD,” we mean United States dollars.

• when we refer to “CHF,” we mean Swiss francs.

Introduction

Trust preferred securities will provide you with rights to distributions and redemption and liquidation payments that are similar to those to which you would be entitled if you had purchased the most senior ranking noncumulative perpetual preferred shares issued directly by UBS AG that have financial terms equivalent to those of the related company preferred securities. The diagram to the right outlines the relationship among investors in trust preferred securities, the relevant UBS Preferred Funding Trust, the related UBS Preferred Funding Company and UBS AG following the completion of an offering.

Each UBS Preferred Funding Trust will pass through to you any dividends, redemption payments or liquidation payments that it receives from the related UBS Preferred Funding Company on related company preferred securities.

UBS AG will guarantee, on a subordinated basis, dividend, redemption and liquidation payment obligations under any company preferred securities.

The UBS Preferred Funding Companies will receive payments under related subordinated notes issued by the Cayman Islands branch of UBS AG and will pay dividends on their company preferred securities that are similar to dividends that would be paid on the most senior ranking noncumulative perpetual preferred shares issued directly by UBS AG that have equivalent financial terms.

The capital raised in any offering will qualify as consolidated Tier 1 capital for UBS under the relevant regulatory capital guidelines of the Swiss Federal Banking Commission.

[FLOW CHART DESCRIBING THE ABOVE FLOW OF FUNDS BETWEEN THE UBS AG, THE UBS PREFERRED FUNDING COMPANIES AND UBS PREFERRED FUNDING TRUST AND RELATIONSHIP BETWEEN THE ABOVE SECURITIES]

1

Cautionary Note Regarding Forward-Looking Statements

This prospectus contains or incorporates statements that constitute “forward-looking statements” within the meaning of Section 21E of the United States Securities Exchange Act of 1934, as amended. The Private Securities Litigation Reform Act of 1995 provides a “safe harbor” for forward-looking information to encourage companies to provide prospective information about themselves without fear of litigation so long as the information is identified as forward looking and is accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from those projected in the information. The words “anticipate”, “believe”, “expect”, “estimate”, “intend”, “plan”, “should”, “could”, “may” and other similar expressions are used in connection with forward-looking statements. In this prospectus and the incorporated documents, forward-looking statements may, without limitation, relate to:

•  The implementation of strategic initiatives, such as the implementation of the European wealth management strategy and our plans to continue to expand our corporate finance business.

•  The development of revenues overall and within specific business areas.

•  The development of operating expenses.

•  The anticipated level of capital expenditures and associated depreciation expense.

•  The expected impact of the risks that affect UBS’s business, including the risk of loss resulting from the default of an obligor or counterparty.

•  Expected credit losses based upon UBS’s credit review.

•  Other statements relating to UBS’s future business development and economic performance.

There can be no assurance that forward-looking statements will approximate actual experience. Several important factors exist that could cause UBS’s actual results to differ materially from expected results as described in the forward-looking statements. Those factors include:

•  General economic conditions, including prevailing interest rates and performance of financial markets, which may affect demand for products and services and the value of our assets.

•  Changes in UBS’s expenses associated with acquisitions and dispositions.

•  General competitive factors, locally, nationally, regionally and globally.

•  Industry consolidation and competition.

•  Changes affecting the banking industry generally and UBS’s banking operations specifically, including asset quality.

•  Developments in technology.

•  Credit ratings and the financial position of obligors and counterparties.

•  UBS’s ability to control risk in its businesses.

•  Changes in tax laws in the countries in which UBS operates, which could adversely affect the tax advantages of certain of UBS’s products or subject it to increased taxation.

2

•  Changes in accounting standards applicable to UBS, as more fully described in this prospectus and the incorporated documents.

•  Changes in investor confidence in the future performance of financial markets, affecting the level of transactions they undertake, and hence the levels of transaction-based fees UBS earns.

•  Changes in the market value of securities held by UBS’s clients, affecting the level of asset based fees UBS can earn on the services it provides.

•  Changes in currency exchange rates, including the exchange rate for the Swiss franc into U.S. dollars.

You should also consider other risks and uncertainties discussed in the documents that are incorporated by reference into this prospectus.

UBS is not under any obligation to (and expressly disclaims any such obligation to) update or alter its forward-looking statements, whether as a result of new information, future events or otherwise.

3

Incorporation of Information About UBS AG

The SEC allows us to “incorporate by reference” into this prospectus the information that we file with them, which means that:

•  The incorporated documents are considered part of this prospectus.

•  We can disclose important information to you by referring you to those documents.

•  Information that we file with the SEC from time to time will automatically be considered to update and supersede the information in this prospectus.

We incorporate by reference in this prospectus.

•  UBS AG’s Annual Report on Form 20-F for the year ended December 31, 2005, which UBS AG filed with the SEC on March 21, 2006.

All subsequent reports that we file on Form 20-F under the Securities Exchange Act of 1934 prior to the termination of this offering will also be deemed to be incorporated by reference into this prospectus. We may also incorporate any other Form 6-K that we submit to the SEC on or after the date of this prospectus and prior to the termination of this offering if the Form 6-K filing specifically states that it is incorporated by reference into this prospectus.

Any statement in this prospectus contained in a document incorporated or deemed to be incorporated by reference into this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement in this prospectus or in any later filed document modifies or supercedes that statement. Any statement that is modified or superseded in this manner will no longer be a part of this prospectus, except as modified or superseded.

You may request a copy, at no cost, of any or all of the documents that are incorporated by reference into this prospectus, excluding exhibits (other than those that we specifically incorporate by reference into the documents that you request) by contacting us, orally or in writing, at the following address:

     UBS AG

     Investor Relations

     Bahnhofstrasse 45

     P.O. Box

     CH-8098 Zurich

     Switzerland

     Phone: +41-44-234 41 00

     Fax: +41-44-234 34 15

     E-mail: SH-investorrelations@ubs.com

     Internet: www.ubs.com/investor-relations

4

Where You Can Find More Information

UBS AG files periodic reports and other information with the United States Securities and Exchange Commission. You may read and copy any document that UBS AG files with the SEC at the SEC’s public reference room at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of its public reference room. The SEC also maintains an internet site at http://www.sec.gov that contains reports, proxy and information statements, and other information about issuers like UBS AG that file electronically with the SEC. You may also inspect UBS AG’s SEC reports and other information at the New York Stock Exchange, Inc., 20 Broad Street, New York, New York 10005 and at the American Stock Exchange LLC, 86 Trinity Place, New York, New York 10006.

We have filed a registration statement under the Securities Act of 1933 on Form F-3 with the SEC covering the securities. For further information about the securities and UBS, you should review our registration statement, its exhibits and the documents incorporated by reference into this prospectus. This prospectus summarizes material provisions of the contracts and other documents that we refer you to. Since this prospectus may not contain all the information that you may find important, you should review the full text of these documents. We have included copies of these documents as exhibits to our registration statement.

5

Presentation of Financial Information

UBS’s financial statements, which are incorporated by reference into this prospectus, have been prepared in accordance with International Financial Reporting Standards and are denominated in Swiss francs, or “CHF,” the legal tender of Switzerland.

The tables below set forth, for the periods and dates indicated, information concerning the noon buying rate for the Swiss franc, expressed in United States dollars or “USD,” per one Swiss franc. The “noon buying rate” is the rate in New York City for cable transfers in foreign currencies as certified for customs purposes by the Federal Reserve Bank of New York. On March 24, 2006 the noon buying rate was 0.7634 USD per 1 CHF.

					(USD per 1 CHF)
Year Ended 31 December	High		Low		Average Rate(1)		At Period End
2001		0.6331		0.5495		0.5910		0.5857
2002		0.7229		0.5817		0.6453		0.7229
2003		0.8189		0.7048		0.7493		0.8069
2004		0.8843		0.7601		0.8059		0.8712
2005		0.8721		0.7544		0.8039		0.7606

Month	High		Low
September 2005		0.8139		0.7712
October 2005		0.7855		0.7679
November 2005		0.7825		0.7544
December 2005		0.7820		0.7570
January 2005		0.7940		0.7729
February 2005		0.7788		0.7575

(1)  The average of the noon buying rates on the last business day of each full month during the relevant period.

6

Limitations on Enforcement of U.S. Laws Against UBS AG,

Its Management and Others

UBS AG is a Swiss bank. Many of its directors and executive officers, including the majority of the persons who signed the registration statement of which this prospectus is a part, and certain experts named in this prospectus, are resident outside the United States, and all or a substantial portion of our assets and the assets of those persons are located outside the United States. As a result, it may be difficult for you to serve legal process on UBS AG or its management or have any of them appear in a U.S. court. We have been advised by UBS internal counsel, that there is doubt as to the enforceability in Switzerland, in original actions or in actions for enforcement of judgments of U.S. courts, of liabilities based solely on the federal securities laws of the United States.

Capitalization of UBS

The following table sets forth the consolidated capitalization of UBS in accordance with International Financial Reporting Standards (IFRS) and translated into U.S. dollars.

		Actual
As of December 31, 2005		CHF		USD
		(in millions)
Debt
	Debt issued(1)		270,434		205,663
	Total Debt		270,434		205,663
Minority Interest(2)			7,619		5,794
Shareholders’ Equity			44,324		33,708
Total capitalization			322,377		245,165

(1) Includes Money Market Paper and Medium Term Notes as per Balance Sheet position.

(2) Includes Trust Preferred Securities. Under IFRS, trust preferred securities are equity instruments held by third parties and are treated as minority interests, with dividends paid also reported in equity attributable to minority interests. Under US GAAP, these entities are not consolidated, and the UBS-issued debt is recognized as a liability in the UBS Group Financial Statements, with interest paid reported in interest expense. See Note 41 to our Financial Report included in our Annual Report on Form 20-F for the year ended December 31, 2005, incorporated by reference into this prospectus.

Swiss franc (CHF) amounts have been translated into U.S. dollars (USD) at the rate of CHF 1 = USD 0.76049.

7

UBS

OVERVIEW

UBS is one of the world’s leading financial firms, serving a discerning global client base. As an organization, it combines financial strength with a culture that embraces change. As an integrated firm, UBS creates added value for clients by drawing on the combined resources and expertise of all its businesses.

UBS is the world’s leading wealth management business, a global investment banking and securities firm with a strong institutional and corporate client franchise, a key asset manager and the market leader in Swiss corporate and individual client banking.

On December 31, 2005, UBS employed more than 69,500 people. With headquarters in Zurich, Switzerland and Basel, Switzerland, UBS operates in 50 countries and from all major financial centers worldwide.

UBS is managed through three Business Groups and its Corporate Center, each of which is summarized below.

For further information about UBS, including more detailed descriptions of the Business Groups and Corporate Center, see “Where You Can Find More Information.”

Global Wealth Management & Business Banking

With more than 140 years of experience, our global wealth management business provides a comprehensive range of products and services individually tailored for wealthy clients around the world. With roughly 4,154 client advisors and more than CHF 1.7 trillion in invested assets, the business consistently delivers high-quality, individually tailored solutions through a global network of 111 offices in Switzerland and 72 offices worldwide. In the United States, it is one of the top wealth managers.

Business Banking Switzerland is the market leader in Switzerland, providing a complete set of banking and securities services for individual and corporate clients. It has around 2.6 million individual clients through more than 3 million accounts, mortgages and other financial relationships, and relationships with around some 136,500 corporate clients, including institutional investors, public entities and foundations, as well as 3,000 financial institutions worldwide.

Global Asset Management

The Global Asset Management business is one of the world’s leading asset managers, providing traditional and alternative investment solutions to financial intermediaries and institutional investors. The breadth, depth and scope of its varied investment capabilities enable it to offer innovative solutions in nearly every asset class. Invested assets totaled over CHF 750 billion on December 31, 2005, making it one of the largest global institutional asset managers, the second largest mutual fund manager in Europe, and the largest mutual fund manager in Switzerland.

Investment Bank

UBS’s Investment Bank is one of the world’s leading firms in the investment banking and securities business, providing a full spectrum of services to institutional and corporate clients, governments and financial intermediaries. Its salespeople, research analysts and investment bankers provide products and services to the world’s key institutional investors, intermediaries, banks, insurance companies,

8

UBS

corporations, sovereign governments, supranational organizations and private investors. For both its own corporate and institutional clients and the individual clients of other parts of UBS, the Investment Bank provides product innovation, research and advice, and comprehensive access to the world’s capital markets.

Corporate Center

Corporate Center creates sustainable value for shareholders and stakeholders by partnering with the Business Groups to ensure that the firm operates as an effective and integrated whole with a common vision and set of values.

Industrial Holdings

Industrial Holdings comprises UBS’s private equity investments and the firm’s majority stake in Motor-Columbus, a financial holding company whose only significant asset is an interest in the Atel Group (Aare-Tessin Ltd. for Electricity). In late September 2005, UBS announced that it would sell its 55.6% stake in Motor-Columbus to a consortium of Atel’s Swiss minority shareholders, EOS Holding and Atel, as well as to French utility Electricité de France (EDF), after corresponding agreements to that effect were signed. At the end of February, the European Commission and the Swiss Competition Commission have cleared the acquisition of the participation held by UBS. At the date of the print order of this Annual Report (8 March 2006), the transaction is expected to be completed as soon as all contractual conditions have been met and the boards of the buyers have passed the appropriate revolutions.

Corporate Information

The legal and commercial name of the company is UBS AG. The company was incorporated under the name SBC AG on February 28, 1978 for an unlimited duration and entered in the Commercial Register of Canton Basle-City on that day. On December 8, 1997, the Company changed its name to UBS AG. The company in its present form was created on June 29, 1998 by the merger of Union Bank of Switzerland (founded 1862) and Swiss Bank Corporation (founded 1872). UBS AG is entered in the Commercial Registers of Canton Zurich and Canton Basle-City. The registration number is CH-270.3.004.646-4.

UBS AG is incorporated and domiciled in Switzerland and operates under Swiss Company Law and Swiss Federal Banking Law as an Aktiengesellschaft, a corporation that has issued shares of common stock to investors.

The address and telephone number of UBS’s two registered offices and principal places of business are: Bahnhofstrasse 45, CH-8098 Zurich, Switzerland, telephone +41-44-234 11 11; and Aeschenvorstadt 1, CH-4051 Basel, Switzerland, telephone +41-61-288 20 20.

UBS shares are listed on the SWX Swiss Exchange and traded through virt-x, which is majority owned by the SWX Swiss Exchange. They are also listed on the New York Stock Exchange and on the Tokyo Stock Exchange.

9

UBS

The UBS Preferred Funding Trusts

Each UBS Preferred Funding Trust is a statutory trust that UBS AG created under the Delaware Statutory Trust Act pursuant to an initial trust agreement entered into by UBS AG and by the filing of a certificate of trust with the Secretary of State of the State of Delaware. Before trust preferred securities are issued, the trust agreement for the relevant Issuer Trust will be amended and restated in its entirety substantially in the form filed with our SEC registration statement. We will qualify the Amended and Restated Trust Agreements as indentures under the Trust Indenture Act of 1939, as amended. We intend to treat each UBS Preferred Funding Trust as a grantor trust for United States federal income tax purposes, meaning that investors in trust preferred securities will generally be treated as if they owned their proportionate shares of the related company preferred securities owned by the relevant UBS Preferred Funding Trust.

UBS AG formed each UBS Preferred Funding Trust for the exclusive purpose of:

•  issuing trust preferred securities,

•  investing the proceeds of such trust preferred securities in related company preferred securities, which benefit from a related UBS AG subordinated guarantee, and

•  engaging in any necessary or incidental activities.

The only assets of each UBS Preferred Funding Trust will be company preferred securities and the related rights of the relevant UBS Preferred Funding Trust under the related UBS AG subordinated guarantee. The Amended and Restated Trust Agreements will not permit any UBS Preferred Funding Trust to acquire any other assets, issue any other equity securities or any debt securities, or engage in any other activities. All expenses and liabilities of each UBS Preferred Funding Trust will be paid by the Stamford branch of UBS AG, except that if the trustee of any UBS Preferred Funding Trust incurs fees, charges or expenses at the request of a holder of its trust preferred securities or other person for which such UBS Preferred Funding Trust is not otherwise liable under its Amended and Restated Trust Agreement, that holder or other person will be liable for such fees, charges and expenses.

The total pro forma capitalization of each UBS Preferred Funding Trust, as adjusted to give effect to a particular offering of trust preferred securities and the use of the proceeds from such offering, will be set forth in the applicable prospectus supplement.

The Amended and Restated Trust Agreements will provide that, to the fullest extent permitted by law, without the need for any other action of any person, including the trustees or any other holder of trust preferred securities, each holder of trust preferred securities will be entitled to enforce, in the name of the relevant UBS Preferred Funding Trust, the rights of such UBS Preferred Funding Trust under the related company preferred securities and the related UBS AG subordinated guarantee represented by the trust preferred securities held by such holder. A holder of trust preferred securities may at any time upon written notice withdraw and hold directly the related company preferred securities represented by such trust preferred securities, in which case such holder will be entitled to directly enforce its rights under the related UBS AG subordinated guarantee.

The principal executive offices of each UBS Preferred Funding Trust is located at c/o Wilmington Trust Company, 1100 North Market Street, Wilmington, Delaware 19890.

10

The UBS Preferred Funding Companies

Introduction

Each UBS Preferred Funding Company is a limited liability company that UBS AG formed under the Delaware Limited Liability Company Act pursuant to an initial limited liability company agreement entered into by UBS AG and by filing a certificate of formation with the Secretary of State of the State of Delaware. We will continue each UBS Preferred Funding Company pursuant to Amended and Restated Limited Liability Company Agreements, which we sometimes refer to as the LLC Agreements. Each UBS Preferred Funding Company will be treated as a partnership for U.S. federal income tax purposes.

UBS AG formed each UBS Preferred Funding Company for the exclusive purpose of:

•  issuing its company common securities to UBS AG,

•  issuing its company preferred securities, initially to the related UBS Preferred Funding Trust,

•  investing the proceeds of the company common securities and the company preferred securities in (1) initially, related subordinated notes issued by the Cayman Islands branch of UBS AG with an aggregate principal amount which, for each UBS Preferred Funding Company, will be set forth in the applicable prospectus supplement and (2) other securities issued by UBS AG acting through a branch, agency or other office located outside of the United States or by a non-U.S. branch of a non-U.S. subsidiary of UBS AG (together, “eligible investments”), and

•  engaging in any related or incidental activities.

The total pro forma capitalization of each UBS Preferred Funding Company, as adjusted to give effect to the offering of its company preferred securities, will be set forth in the applicable prospectus supplement.

Each UBS Preferred Funding Company will apply the income generated by the related subordinated notes and other eligible investments to pay dividends to the related UBS Preferred Funding Trust, as holder of its company preferred securities, and UBS AG, as holder of its company common securities. The related UBS Preferred Funding Trust will then pass the dividends it receives on the company preferred securities through to the holders of its trust preferred securities as distributions on its trust preferred securities.

UBS AG will purchase all of the company common securities of each UBS Preferred Funding Company for an amount which will be set forth in the applicable prospectus supplement. We intend to treat the company preferred securities as Tier 1 capital for purposes of the relevant regulatory capital guidelines of the Swiss Federal Banking Commission. We will agree with each UBS Preferred Funding Company in the LLC Agreement that, as long as any company preferred securities are outstanding, UBS AG will continue to own, directly or indirectly, 100% of the outstanding company common securities of each such UBS Preferred Funding Company. Each UBS Preferred Funding Company will also covenant to maintain “UBS” as part of its name for as long as any trust preferred securities of the related UBS Preferred Funding Trust remain outstanding unless, because of a merger or other business combination involving UBS AG or a change by UBS AG of its own name, inclusion of “UBS” as part of any UBS Preferred Funding Company’s name is no longer appropriate.

We will also agree in the LLC Agreements that it will from time to time either (i) contribute (or cause others, including the Stamford branch of UBS AG, to contribute) to each UBS Preferred Funding Company such additional funds as are necessary in order to enable such UBS Preferred Funding Company to pay its operating expenses on or before any date when any such operating expenses are

11

The UBS Preferred Funding Companies

due or (ii) directly pay such UBS Preferred Funding Company’s operating expenses then due and payable and not otherwise paid. “Operating expenses” generally means all expenses and obligations of the relevant UBS Preferred Funding Company, but does not include any payments on its company preferred securities or company common securities.

The principal executive offices of each UBS Preferred Funding Company is located at Corporation Service Company, 2711 Centerville Road, Wilmington, Delaware 19808.

Activities of the UBS Preferred Funding Companies

General

Each UBS Preferred Funding Company’s principal business objective is to acquire and hold eligible investments, which will include:

•  initially, subordinated notes issued by the Cayman Islands branch of UBS AG with an aggregate principal amount as set forth in the applicable prospectus supplement, and

•  other securities issued by us acting through a branch, agency or other office located outside of the United States or by a non-U.S. branch of a non-U.S. subsidiary of ours.

Each UBS Preferred Funding Company will apply the net income generated by the subordinated notes and other eligible investments to pay dividends to the related UBS Preferred Funding Trust, as holder of company preferred securities, and us, as holder of the company common securities. The related UBS Preferred Funding Trust will then pass through the dividends it receives on the related company preferred securities to the holders of its trust preferred securities as distributions on its trust preferred securities. Each UBS Preferred Funding Company may (with the consent of the holders of two-thirds (based on the aggregate liquidation preference) of its company preferred securities and company parity preferred securities, voting together as a single class) issue additional preferred securities as described under “Description of Company Preferred Securities.”

Dividends

We currently expect each UBS Preferred Funding Company to pay an aggregate amount of dividends with respect to its outstanding company common securities and company preferred securities equal to approximately 100% of the interest and other income it receives on the subordinated notes and any other eligible investments.

The LLC Agreement of each UBS Preferred Funding Company will:

•  preclude each UBS Preferred Funding Company from incurring any indebtedness for borrowed money, and

•  require the approval of the holders of at least 66²/3 % of each UBS Preferred Funding Company’s outstanding company preferred securities and any outstanding company parity preferred securities (based on the aggregate liquidation preference), voting together as a single class, before dividends on its company preferred securities can be paid out of any source other than interest income received on the subordinated notes or interest or dividend income received on its other eligible investments.

Under the Delaware Limited Liability Company Act, no UBS Preferred Funding Company may pay dividends or other distributions on its company common securities or company preferred securities—even if such payments are “mandatory”—if, after making the distributions, such UBS Preferred Funding Company’s liabilities would exceed the fair value of its assets. However, no UBS Preferred Funding Company is expected to have any material liabilities, so this restriction is unlikely to affect the ability of any UBS preferred funding company to pay dividends on its company preferred securities.

12

The UBS Preferred Funding Companies

Dividends on company preferred securities will in any event be required to be paid up to the mandatory dividend payment amount on any mandatory dividend payment date, unless there is a capital limitation on such date. See “Description of Company Preferred Securities— Dividends— Mandatory Dividends.”

Investment Policies

Each UBS Preferred Funding Company’s initial investment policies will be established pursuant to its respective LLC Agreement. Under these investment policies, no UBS Preferred Funding Company may hold or invest in any securities other than eligible investments as described above under “—Introduction.”

The investment policies will require that:

•  the terms of any eligible investments other than subordinated notes purchased by any UBS Preferred Funding Company be established in good faith and, to the extent deemed advisable by UBS AG, reflect arm’s-length terms at the time of purchase, and the purchase by any UBS Preferred Funding Company of such eligible investments be approved by the affirmative vote of a majority of its entire board of directors, and

•  each UBS Preferred Funding Company maintain its assets in a manner that will not require such UBS Preferred Funding Company to be registered as an investment company under the Investment Company Act of 1940.

The investment policies of any UBS Preferred Funding Company may be amended only by the affirmative vote of the holders of at least 66²/3 % of its outstanding company preferred securities and any of its outstanding company parity preferred securities (based on the aggregate liquidation preference), voting together as a single class. Although we do not anticipate that any UBS Preferred Funding Company will sell subordinated notes (and no market for them is expected to develop), were any UBS Preferred Funding Company to do so, such UBS Preferred Funding Company would be required to invest the proceeds of the sale in accordance with such UBS Preferred Funding Company’s investment policies as they exist at the time of such sale.

Administration Agreements

Before issuing company preferred securities, each UBS Preferred Funding Company will enter into an administration agreement with the Stamford branch of UBS AG, under which the Stamford branch will provide (or causes others to provide) accounting, legal, tax and other support services to each UBS Preferred Funding Company, assists each such UBS Preferred Funding Company in complying with pertinent U.S. and Swiss local, state and federal laws, and provides administrative, record keeping and secretarial services to each such UBS Preferred Funding Company. Under the administration agreement, each UBS Preferred Funding Company will agree to reimburse the provider of these services for the value of services provided by such provider to such UBS Preferred Funding Company on an arm’s-length basis.

Each UBS Preferred Funding Company will maintain company records that are separate from those of UBS AG or any of its affiliates. None of the officers, employees or directors of any UBS Preferred Funding Company will have any direct or indirect pecuniary interest in any security to be acquired or disposed of by such UBS Preferred Funding Company or in any transaction in which such UBS Preferred Funding Company has an interest.

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The UBS Preferred Funding Companies

Management of the UBS Preferred Funding Companies

Directors and Executive Officers

The initial LLC Agreement of each UBS Preferred Funding Company provides that its board of directors will at all times include not less than two and not more than five members. The board of directors will initially have two members. The directors will be designated as “managers” of the UBS Preferred Funding Company within the meaning of the Delaware Limited Liability Company Act. The directors will serve until their successors are duly elected and qualified.

Each UBS Preferred Funding Company will have at least three officers. The names of the initial directors and executive officers of each UBS Preferred Funding Company will be set forth in the applicable prospectus supplement.

It is anticipated all of the officers of each UBS Preferred Funding Company will also be officers or employees of UBS AG or its affiliates.

Additional Directors

If at any time the aggregate of unpaid dividends on the company preferred securities or any company parity preferred securities of any UBS Preferred Funding Company equals or exceeds an amount equal to a certain number of regularly scheduled dividend payments specified in the applicable prospectus supplement, the holders of its company preferred securities and any company parity preferred securities, voting together as a single class, will have the exclusive right to elect two additional directors. Holders of a majority (based on the aggregate liquidation preference) of its company preferred securities and company parity preferred securities may exercise this right by written consent or at a meeting of such holders called for such purpose. The LLC Agreement of each UBS Preferred Funding Company provides that this meeting may be called at the request of holders of 25% (based on the aggregate liquidation preference) of its company preferred securities or company parity preferred securities. This right will continue either until all unpaid dividends have been paid in full or until full dividends have been paid on its company preferred securities for the number of consecutive dividend periods specified in the applicable prospectus supplement. While this right continues, any vacancy in the office of the additional directors may be filled only by the holders of company preferred securities and company parity preferred securities voting as described above.

Indemnification and Insurance for Directors

The LLC Agreement of each UBS Preferred Funding Company will provide that:

•  its directors have no personal liability to the UBS Preferred Funding Company or the holders of its company common securities or company preferred securities for monetary damages (i) for voting not to take enforcement action with respect to the subordinated notes or any other eligible investments owned by the UBS Preferred Funding Company, or (ii) at any time for breach of any such director’s fiduciary duty, if any, except for such director’s gross negligence or willful misconduct,

•  the UBS Preferred Funding Company will indemnify any director or officer for any liability and related expenses, including reasonable counsel’s fees, arising out of such director’s or officer’s status as a director or officer of the UBS Preferred Funding Company, except for liability determined by a court of competent jurisdiction to have arisen out of such director’s or officer’s gross negligence or willful misconduct,

•  the right to indemnification is a contract right and the LLC Agreement will set forth certain procedural and evidentiary standards applicable to the enforcement of a claim under the LLC Agreement of the UBS Preferred Funding Company, and

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The UBS Preferred Funding Companies

•  the UBS Preferred Funding Company may purchase and maintain insurance to protect any director or officer against any liability asserted against, or incurred by, him or her, arising out of his or her status as a director or officer.

Common Securities of the UBS Preferred Funding Companies

Holders of company common securities of a UBS Preferred Funding Company will receive dividends out of interest payments received by such UBS Preferred Funding Company on the subordinated notes and its other eligible investments, if any, not required to be applied to fund dividends with respect to its company preferred securities or expenses of such UBS Preferred Funding Company. However, as long as any company preferred securities or company parity preferred securities of such UBS Preferred Funding Company are outstanding, no dividends or other distributions (including redemptions and purchases) may be made with respect to its company common securities unless full dividends on all series of its company preferred securities have been paid (except as otherwise described under “Description of Company Preferred Securities—Ranking and Liquidation Preference”). See “Description of Company Preferred Securities—Dividends.”

Subject to the rights, if any, of the holders of company preferred securities (to the limited extent described herein) and any other series of company parity preferred securities, all voting rights will be vested in the company common securities. Holders of company common securities will be entitled to vote in proportion to the stated amounts represented by their company common securities. All issued and outstanding shares of company common securities are and will be held by UBS AG.

If any UBS Preferred Funding Company dissolves, liquidates or winds up (whether voluntary or involuntary) after all debts and liabilities of such UBS Preferred Funding Company have been satisfied and there have been paid or set aside for the holders of its company preferred securities the full preferential amounts to which such holders are entitled, the holders of its company common securities will be entitled to share equally and ratably in any assets remaining.

Preferred Securities of the UBS Preferred Funding Companies

Subject to limitations prescribed by Delaware law and each UBS Preferred Funding Company’s LLC Agreement, the board of directors of each UBS Preferred Funding Company or, if then constituted, a duly authorized committee of the board of directors is authorized to issue (with the consent of the holders of two-thirds (based on the aggregate liquidation preference) of its company preferred securities and company parity preferred securities, voting together as a single class), from the authorized but unissued capital shares of the UBS Preferred Funding Company, additional series of preferred securities of the UBS Preferred Funding Company ranking on a parity with its company preferred securities in such series as the board of directors (or committee) may determine and to establish, from time to time, the number or amount by aggregate liquidation preference of shares (if applicable) of such series to be included in any such series and to fix the designation and any preferences, conversion and other rights, voting powers, restrictions, limitations as to dividends, qualifications and terms and conditions of redemption of the securities of any such series, and such other subjects or matters as may be fixed by resolution of the board of directors. However, each UBS Preferred Funding Company’s LLC Agreement will preclude:

•  the issuance of any other classes or series of equity securities that are senior to its company preferred securities, either as to dividends or as to rights upon dissolution, liquidation or winding up of the UBS Preferred Funding Company, without the approval of each holder of its company preferred securities, and

•  the issuance of any company parity preferred securities without the approval of 66²/3 % of the holders of its company preferred securities and unless the related UBS AG subordinated

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The UBS Preferred Funding Companies

guarantee is amended so that such additional company parity preferred securities benefit from the related UBS AG subordinated guarantee in substantially the same manner as its company preferred securities without any adverse effect on the holders of its company preferred securities. See “Description of Company Preferred Securities—Voting Rights.”

No additional payments will be required pursuant to the Delaware Limited Liability Company Act for any company parity preferred securities to represent limited liability company interests in any UBS Preferred Funding Company upon issuance against full payment of the purchase price for such company parity preferred securities. The specific terms of a particular series of company parity preferred securities will be described in the certificate of designation (as defined in each UBS Preferred Funding Company’s LLC Agreement) to be incorporated into each UBS Preferred Funding Company’s LLC Agreement relating to that series, except in the case of shares of company preferred securities where the terms thereof will be set forth in each UBS Preferred Funding Company’s LLC Agreement.

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Use of Proceeds

Each UBS Preferred Funding Trust will use the proceeds from the sale of its trust preferred securities to purchase the related company preferred securities from the related UBS Preferred Funding Company.

The related UBS Preferred Funding Company will use the proceeds from the sale of its company preferred securities to the related UBS Preferred Funding Trust and from the sale of its company common securities to UBS AG to acquire the related subordinated notes issued by the Cayman Islands branch of UBS AG and to pay certain expenses related to the particular offering. See “The UBS Preferred Funding Companies—Activities of the UBS Preferred Funding Companies.”

Unless the applicable prospectus supplement states otherwise, UBS AG will use the proceeds from the sale of subordinated notes issued by its Cayman Islands branch for general corporate purposes outside of Switzerland.

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Description of Trust Preferred Securities

Each UBS Preferred Funding Trust will issue its trust preferred securities under the terms of its Amended and Restated Trust Agreement. We will qualify the Amended and Restated Trust Agreements as indentures under the Trust Indenture Act. The terms of any trust preferred securities will include both those stated in the relevant Amended and Restated Trust Agreement and the Delaware Statutory Trust Act and those made part of the relevant Amended and Restated Trust Agreement by the Trust Indenture Act. The following summary of the material terms and provisions of the trust preferred securities is not complete and is subject to, and qualified in its entirety by reference to, the Amended and Restated Trust Agreements of each UBS Preferred Funding Trust, the Delaware Statutory Trust Act and the Trust Indenture Act. We have filed a copy of a form of Amended and Restated Trust Agreement applicable for each UBS Preferred Funding Trust as an exhibit to the registration statement of which this prospectus is a part, which may be modified or otherwise amended as described in the applicable prospectus supplement.

General

Any trust preferred securities will be certificates of beneficial interest in the assets of the relevant UBS Preferred Funding Trust, the terms of which are set forth in the applicable Amended and Restated Trust Agreement and applicable prospectus supplement.

Unless otherwise specified in the applicable prospectus supplement, any trust preferred securities will be issued in denominations of USD25 in the case of an offering of trust preferred securities to retail investors or USD1000 or a larger denomination in the case of an offering of trust preferred securities to institutional investors, liquidation amount and whole-number multiples of USD25 or USD1000, as the case may be. The aggregate liquidation amount of the trust preferred securities to be offered will be specified in the applicable prospectus supplement. Each trust preferred security will represent a corresponding amount of related company preferred securities, together with related rights under a UBS AG subordinated guarantee.

The trustee of each UBS Preferred Funding Trust will hold the related company preferred securities and the related rights under the relevant UBS AG subordinated guarantee deposited in each such UBS Preferred Funding Trust for the benefit of the holders of the trust preferred securities. Each Amended and Restated Trust Agreement provides that, to the fullest extent permitted by law, without the need for any other action of any person, including the trustee or any other holder of trust preferred securities, each holder of trust preferred securities will be entitled to enforce, in the name of the relevant UBS Preferred Funding Trust, the rights of such UBS Preferred Funding Trust under the related company preferred securities and the related rights under the relevant UBS AG subordinated guarantee represented by the trust preferred securities held by such holder. Trust preferred securities may be exchanged for the related company preferred securities as described under “—Withdrawal of Company Preferred Securities.”

The funds of any UBS Preferred Funding Trust available for distribution to the holders of its trust preferred securities will be limited to payments received from the related UBS Preferred Funding Company as dividends, redemption payments and liquidation payments on the related company preferred securities and to payments received from UBS AG pursuant to the related UBS AG subordinated guarantee of those payments. See “Description of Company Preferred Securities.” Each UBS Preferred Funding Trust will distribute such payments, upon their receipt, to the holders of its trust preferred securities on a pro rata basis. If any UBS Preferred Funding Company does not pay any regularly scheduled dividend on its company preferred securities when it is required to and UBS AG does not perform its obligations under the related UBS AG subordinated guarantee, the related UBS Preferred Funding Trust will not have sufficient funds to make the related regularly scheduled distribution payment on its trust preferred securities.

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Description of Trust Preferred Securities

The trust preferred securities may be listed on one or more securities exchanges (including the New York Stock Exchange and the Luxembourg Stock Exchange) or on no securities exchange, as specified in the applicable prospectus supplement.

Distributions

Each trust preferred security will represent a corresponding amount of related company preferred securities, together with the related rights under the relevant UBS AG subordinated guarantee. Each UBS Preferred Funding Trust will make regularly scheduled distributions or other mandatory distributions on its trust preferred securities concurrently with, and in the same amount as, the regularly scheduled dividends or special dividends on the related company preferred securities. See “Description of Company Preferred Securities—Dividends.” Accordingly, to the extent that dividends are paid on the related company preferred securities, distributions on trust preferred securities will accrue from the date of original issue and be paid on the liquidation amount of the relevant trust preferred securities in arrears on the dividend payment dates regularly scheduled to occur on the dates and at the rate specified in the applicable prospectus supplement.

For details on the calculation and payment of dividends, see “Description of Company Preferred Securities—Dividends” and the applicable prospectus supplement. Whenever, and to the extent, any UBS Preferred Funding Trust receives any cash payments representing a regularly scheduled dividend, special dividend or redemption payment on the related company preferred securities, such UBS Preferred Funding Trust will distribute such amounts to the holders of its trust preferred securities in proportion to their liquidation amounts. Each regularly scheduled or special distribution on any trust preferred securities will be payable to holders of record as they appear on the securities register of the relevant UBS Preferred Funding Trust on the corresponding record date. The record dates for trust preferred securities will be the fifteenth day (whether or not a business day) prior to the relevant regularly scheduled or other distribution date.

If any distribution would be payable on a day that is not a business day, that distribution will instead be made on the next business day. No interest or other payment will be due as a result of any such delay.

If dividends are not payable on the related company preferred securities on any dividend payment date for the reasons described in “Description of Company Preferred Securities—Dividends,” then the holders of trust preferred securities will not be entitled to receive a distribution on that date.

Redemption

Trust preferred securities will be redeemable only upon redemption of the related company preferred securities.

If any UBS Preferred Funding Company redeems its company preferred securities in accordance with its LLC Agreement as described under “Description of Company Preferred Securities—Redemption,” then such UBS Preferred Funding Company must give the trustee of the related UBS Preferred Funding Trust at least 30 days’ prior notice before doing so. The trustee will mail the notice of redemption not less than 25 days prior to the date fixed for redemption of the related company preferred securities to the holders of its trust preferred securities as provided under “—Notices.”

On the date of redemption of any company preferred securities, so long as the relevant UBS Preferred Funding Company or UBS AG has deposited with Wilmington Trust Company, the paying agent, on behalf of the related UBS Preferred Funding Trust the aggregate amount payable upon redemption of all its company preferred securities held by such UBS Preferred Funding Trust to be redeemed, the paying agent on behalf of such UBS Preferred Funding Trust will irrevocably deposit with The

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Description of Trust Preferred Securities

Depository Trust Company (“DTC”) funds sufficient to pay the redemption price and give DTC irrevocable instructions to pay the redemption price to the holders of the trust preferred securities to be redeemed. See “Book-Entry Issuance of Trust Preferred Securities.” Once the paying agent has received this deposit, all rights of the holders of the trust preferred securities called for redemption will end, except their right to receive the redemption price, without interest. If any date fixed for redemption of any trust preferred securities is not a business day, then the redemption price will instead be paid on the next business day, except that if that business day falls in the next calendar year, the redemption price will be paid on the preceding business day. No interest or other payment will be due as a result of any such adjustment.

If only some of the outstanding trust preferred securities of a UBS Preferred Funding Trust are to be redeemed, the trust preferred securities to be redeemed will be selected in accordance with DTC’s procedures. See “Book-Entry Issuance of Trust Preferred Securities—DTC’s Procedures for Notices, Voting and Payments.” If any trust preferred securities do not remain registered in the name of DTC or its nominee and only some of the outstanding trust preferred securities of a UBS Preferred Funding Trust are to be redeemed, the trust preferred securities will be redeemed proportionately or, if applicable, selected for redemption pursuant to the rules of any securities exchange on which such trust preferred securities are listed at that time. Each UBS Preferred Funding Company will promptly notify the registrar and transfer agent for its trust preferred securities, in writing, of the trust preferred securities selected for redemption. In addition, for so long as the rules of any securities exchange on which the relevant trust preferred securities are listed so require, notice will be given to such securities exchange of trust preferred securities selected for redemption and published as required by such securities exchange. If any trust preferred securities are listed on the Luxembourg Stock exchange, for as long as the rules of the Luxembourg Stock Exchange so require, notice will be given to the Luxembourg Stock Exchange of any such trust preferred securities selected for redemption and published in a daily newspaper of general circulation in Luxembourg (which is expected to be the Luxemburger Wort).

Withdrawal of Company Preferred Securities

Any beneficial owner of trust preferred securities will be able to withdraw all, but not less than all, of the related company preferred securities represented by such trust preferred securities by providing a written notice to the trustee, with evidence of beneficial ownership in form satisfactory to the trustee and providing to the related UBS Preferred Funding Company such documents or information as such UBS Preferred Funding Company may request for tax reporting purposes. The holder’s notice will also be deemed to be such beneficial owner’s agreement to be subject to the terms of the relevant UBS Preferred Funding Company’s LLC Agreement applicable to the rights of the holders of its company preferred securities.

Within a reasonable period after such a request has been properly made, any trustee must instruct DTC to reduce the amount of trust preferred securities represented by the relevant global certificate by the corresponding amount of related company preferred securities to be so withdrawn by the withdrawing owner. The related UBS Preferred Funding Company will issue to the withdrawing owner a certificate representing the amount of related company preferred securities withdrawn, and the trustee will reduce the amount of trust preferred securities represented by the relevant global certificate accordingly. Company preferred securities will be issued only in certificated fully-registered form and will not be eligible to be held through DTC, Euroclear or Clearstream. Under current U.S. tax reporting rules, holders of company preferred securities will thereafter receive an annual Form K-1 instead of the Form 1099 that holders of trust preferred securities will receive. See “U.S. Tax Considerations—Information Reporting and Backup Withholding Tax.”

Any holder of company preferred securities may redeposit withdrawn company preferred securities by delivering to the relevant trustee the certificates for the company preferred securities to be deposited,

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Description of Trust Preferred Securities

which are (i) if required by the trustee, properly endorsed or accompanied by a properly executed instrument of transfer or endorsement in form satisfactory to the trustee and in compliance with the terms of the relevant UBS Preferred Funding Company’s LLC Agreement and (ii) accompanied by all such certifications as may be required by the trustee in its sole discretion and in accordance with the provisions of the relevant Amended and Restated Trust Agreement. Within a reasonable period after such deposit is properly made, the trustee will instruct DTC to increase the amount of the related trust preferred securities represented by the relevant global certificate accordingly.

Voting Rights

If at any time the holders of any company preferred securities are entitled to vote under any UBS Preferred Funding Company’s LLC Agreement, the trustee will:

•  notify the holders of the related trust preferred securities of such right,

•  request specific direction from each holder of the related trust preferred securities as to the vote with respect to the company preferred securities represented by such trust preferred securities, and

•  vote the relevant company preferred securities only in accordance with such specific direction.

Upon receiving notice of any meeting at which the holders of any company preferred securities are entitled to vote, the relevant trustee will, as soon as practicable, mail to the holders of the related trust preferred securities a notice as provided under “—Notices.” Each UBS Preferred Funding Company will provide the form of notice to the trustee of the related UBS Preferred Funding Trust to be forwarded to the holders of the related trust preferred securities. The notice will contain:

•  all the information that is contained in the notice announcing the meeting of the holders of the company preferred securities,

•  a statement that the holders of the related trust preferred securities will be entitled, subject to any applicable provision of law, to direct the trustee specifically as to the exercise of the voting rights pertaining to the number of related company preferred securities represented by their respective trust preferred securities, and

•  a brief description of the manner in which the holders may give such specific directions.

If any UBS Preferred Funding Trust receives a written direction from a holder of its trust preferred securities, its trustee will vote, or cause to be voted, the amount of related company preferred securities represented by such trust preferred securities in accordance with the instructions set forth in the direction. If the trustee does not receive specific instructions from the holder of any trust preferred securities, the trustee will abstain from voting the related company preferred securities represented by those trust preferred securities.

Any UBS Preferred Funding Company and the trustee of the related UBS Preferred Funding Trust may, without the consent of the holders of the trust preferred securities of the related UBS Preferred Funding Trust, enter into one or more agreements supplemental to the relevant Amended and Restated Trust Agreement, in form satisfactory to the trustee, for any of the following purposes:

•  to evidence the succession of another partnership, corporation or other entity to such UBS Preferred Funding Company and the assumption by any such successor of the covenants of such UBS Preferred Funding Company under the relevant Amended and Restated Trust Agreement,

•  to add to the covenants of such UBS Preferred Funding Company for the benefit of the holders of related trust preferred securities, or to surrender any right or power herein conferred upon such UBS Preferred Funding Company,

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Description of Trust Preferred Securities

•  to correct or supplement any provision of the relevant Amended and Restated Trust Agreement which may be defective or inconsistent with any other provision therein,

•  to make any other provisions with respect to matters or questions arising under the relevant Amended and Restated Trust Agreement, provided that any such action does not materially adversely affect the interests of the holders of trust preferred securities, or

•  to cure any ambiguity or correct any mistake.

Any other amendment or agreement supplemental to any Amended and Restated Trust Agreement must be in writing and approved by the holders of 66²/3 % of the then outstanding trust preferred securities of the relevant UBS Preferred Funding Trust.

Transfer and Issue of Definitive Trust Preferred Securities

Transfer, Issue and Delivery

If trust preferred securities are issued in definitive form (“definitive trust preferred securities”) in the limited circumstances described in “Book-Entry Issuance of Trust Preferred Securities—Termination of and Changes to Depositary Arrangements,” those trust preferred securities may be transferred in any whole-number multiples of USD25, or USD1000, as the case may be, or in such other denominations as may be specified in the applicable prospectus supplement, by surrendering the definitive trust preferred securities certificates together with the form of transfer endorsed on it, duly completed and executed at the office of the transfer agent. The initial transfer agent for all trust preferred securities will be the Wilmington Trust Company. If only part of a definitive trust preferred securities certificate is transferred, a new definitive trust preferred securities certificate representing the securities that are not transferred will be issued to the transferor within three business days after the transfer agent receives the certificate. The new certificate representing the trust preferred securities that were not transferred will be delivered to the transferor by uninsured mail at the risk of the transferor, to the address of the transferor that appears in the records of the relevant UBS Preferred Funding Trust. The new certificate representing the trust preferred securities that were transferred will be sent to the transferee within three business days after the relevant trustee receives the certificate transferred, by uninsured mail at the risk of the holder entitled to the trust preferred securities represented by the certificate, to the address specified in the form of transfer.

Formalities Free of Charge

Registration of transfers of definitive trust preferred securities will be made without charge by any UBS Preferred Funding Trust, but the transferor must pay any tax or other governmental charges that may be imposed in relation to the transfer, together with any indemnity that the relevant UBS Preferred Funding Trust, UBS AG or the transfer agent may require.

Closed Periods

No holder may require the transfer of any trust preferred securities to be registered during the period of 15 days ending on the due date for any payment of principal on such trust preferred securities.

No UBS Preferred Funding Trust will be required to register, or cause others to register, the transfer of any trust preferred securities after such trust preferred securities have been called for redemption.

Regulations Concerning Transfer and Registration

All transfers of definitive trust preferred securities and entries must be made as provided in the agency agreement relating to such trust preferred securities. The provisions of these agreements that govern transfers may be changed by each UBS Preferred Funding Trust with the prior written approval of its trustee.

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Description of Trust Preferred Securities

Registrar and Transfer Agent

Wilmington Trust Company will act as registrar and transfer agent for all trust preferred securities. If and for as long as the trust preferred securities are listed on the Luxembourg Stock Exchange, UBS Preferred Funding Trust will also maintain a transfer agent in Luxembourg. The initial Luxembourg transfer agent will be as specified in the applicable prospectus supplement.

Payments and Paying Agent

As long as trust preferred securities are in book-entry form, payments of interest and principal on such trust preferred securities will be made to DTC, which will credit the relevant accounts at DTC on the scheduled payment dates. The payments of interest and principal will be distributed to participants, indirect participants and beneficial owners of such trust preferred securities as described under “Book-Entry Issuance of Trust Preferred Securities—DTC’s Procedures for Notices, Voting and Payments.”

If definitive trust preferred securities are issued in the limited circumstances described above, payments of interest and principal on such trust preferred securities will be made by check mailed to the address of the holder entitled to receive the payment, as the address appears in the relevant UBS Preferred Funding Trust’s register.

Each UBS Preferred Funding Trust will maintain a paying agent with respect to its trust preferred securities which will initially be the Wilmington Trust Company. The paying agent will be permitted to resign as paying agent upon 30 days’ written notice to the relevant trustee. If Wilmington Trust Company resigns as paying agent, the relevant trustee will appoint another bank or trust company to act as paying agent. If and for as long as the trust preferred securities are listed on the Luxembourg Stock Exchange, UBS Preferred Funding Trust will also maintain a paying agent in Luxembourg. The initial Luxembourg paying agent will be as specified in the applicable prospectus supplement.

Termination of the Amended and Restated Trust Agreements

The Amended and Restated Trust Agreement of each UBS Preferred Funding Trust will terminate upon the earliest to occur of the redemption of all of the trust preferred securities of such UBS Preferred Funding Trust, the delivery of a final distribution of the related company preferred securities to the holders of its trust preferred securities, withdrawal of all related company preferred securities from the UBS Preferred Funding Trust (as described under “—Withdrawal of Company Preferred Securities”) or dissolution of the UBS Preferred Funding Trust as described in the following paragraph.

Each UBS Preferred Funding Company may instruct the trustee of the related UBS Preferred Funding Trust to dissolve such UBS Preferred Funding Trust and to distribute its company preferred securities on a pro rata basis to the holders of trust preferred securities of such UBS Preferred Funding Trust in the case of either a Tax Event as to the related UBS Preferred Funding Trust or an Investment Company Act Event as to the related UBS Preferred Funding Trust, as each is defined under “Description of Company Preferred Securities—Redemption.”

Any company preferred securities held in definitive fully registered form will not be eligible to be held through DTC, Euroclear or Clearstream.

Expenses of the UBS Preferred Funding Trusts

All charges or expenses of each UBS Preferred Funding Trust, including the charges and expenses of the relevant trustees, will be paid by the Stamford branch of UBS AG, except that, if a trustee incurs fees, charges or expenses, for which it is not otherwise liable under the relevant Amended and Restated Trust Agreement, at the request of a holder of trust preferred securities or other person, such holder or other person will be liable for such fees, charges and expenses.

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Description of Trust Preferred Securities

Resignation and Removal of Trustee

Each UBS Preferred Funding Trust will at all times have a trustee that is a bank that has its principal place of business in the State of Delaware and a combined capital and surplus of USD50,000,000. If a trustee ceases to be eligible, it must resign.

The trustee of any UBS Preferred Funding Company may resign as trustee under the relevant Amended and Restated Trust Agreement at any time by giving notice of its resignation to the related UBS Preferred Funding Company. Each trustee may be removed by the related UBS Preferred Funding Company at any time by notice of such removal delivered to the relevant trustee. Any resignation or removal of a trustee will take effect upon the appointment of a qualified successor trustee and the successor’s acceptance of such appointment.

If the trustee of any UBS Preferred Funding Trust shall resign or be removed, the related UBS Preferred Funding Company shall, within 45 days after the delivery of the notice of resignation or removal, as the case may be, appoint a successor trustee, which shall be a bank or trust company, or an affiliate of a bank or trust company, having its principal office in the State of Delaware and having a combined capital and surplus of at least USD50,000,000.

Information Concerning the Trustee

Wilmington Trust Company is the trustee of each UBS Preferred Funding Trust. The trustee is required to perform only those duties that are specifically set forth in the relevant Amended and Restated Trust Agreement, except when a default has occurred and is continuing with respect to the relevant trust preferred securities. After a default, the trustee must exercise the same degree of care a prudent person would exercise under the circumstances in the conduct of his or her own affairs. Subject to these requirements, the trustee is under no obligation to exercise any of the powers vested in it by the relevant Amended and Restated Trust Agreement at the request of any holder of relevant trust preferred securities, unless the holder offers the trustee reasonable indemnity against the costs, expenses and liabilities that might be incurred by exercising those powers.

Notices

Notices to the holders of trust preferred securities will be given by delivery of the relevant notice to DTC, Euroclear, Clearstream and any other relevant securities clearing system for communication by each of them to entitled participants, and, as long as the trust preferred securities of any UBS Preferred Funding Trust are listed on one or more stock exchanges and the rules of such stock exchange(s) so require, notices will also be published in the manner that the rules of such stock exchange(s) may require. In addition, if any trust preferred securities are listed on the Luxembourg Stock Exchange and for as long as the rules of the Luxembourg Stock Exchange so require, notices will be published in a daily newspaper of general circulation in Luxembourg (which is expected to be the Luxemburger Wort).

If any trust preferred securities are no longer held in the name of DTC or its nominee, notice to the holders of such trust preferred securities will also be mailed by first-class mail, postage prepaid, to the holders’ addresses appearing in the records of the relevant UBS Preferred Funding Trust.

Governing Law

Unless stated otherwise in the applicable prospectus supplement, the Amended and Restated Trust Agreements and any trust preferred securities will be governed by the laws of the State of Delaware.

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Description of Company Preferred Securities

Each UBS Preferred Funding Company will issue its company preferred securities under the terms of its Amended and Restated Limited Liability Company Agreement. The following summary of the material terms and provisions of the company preferred securities is not complete and is subject to and qualified in its entirety by reference to the LLC Agreement of each UBS Preferred Funding Company and the Delaware Limited Liability Company Act. We have filed a copy of a form of the LLC Agreement applicable for each UBS Preferred Funding Company as an exhibit to the registration statement of which this prospectus is a part, which may be modified or otherwise amended as described in the applicable prospectus supplement.

General

The company preferred securities will be preferred limited liability company interests in a UBS Preferred Funding Company, the terms of which will be set forth in the applicable UBS Preferred Funding Company’s LLC Agreement and the applicable prospectus supplement.

The company preferred securities are intended to provide holders with rights to distributions and redemption and liquidation payments that are similar to those to which holders would be entitled if they had purchased the most senior ranking noncumulative perpetual preferred shares issued directly by UBS AG that have financial terms equivalent to those of their company preferred securities.

The company preferred securities will be validly issued, and no additional payments will be required for such securities to represent limited liability company interests in the relevant UBS Preferred Funding Company. Holders of company preferred securities will have no preemptive rights with respect to any other securities of the relevant UBS Preferred Funding Company. The company preferred securities will not be convertible into company common securities or any other interests in the relevant UBS Preferred Funding Company and will not be subject to any sinking fund or other obligation of the relevant UBS Preferred Funding Company for their repurchase or retirement.

Unless otherwise specified in the applicable prospectus supplement, the company preferred securities will be issued in certificated form only in denominations of USD25 in the case of an offering of trust preferred securities to retail investors and USD1000 or a larger denomination in the case of an offering of trust preferred securities to institutional investors, liquidation preference and whole-number multiples of USD25 or USD1000, as the case may be. The aggregate liquidation preference of all company preferred securities offered will be specified in the applicable prospectus supplement.

Each UBS Preferred Funding Company has the power to create and issue additional preferred limited liability company interests (i) that are junior to its company preferred securities as to payment of dividends and payments of amounts upon dissolution, liquidation or winding up of such UBS Preferred Funding Company (“company junior securities”) or (ii) that are on a parity with its company preferred securities as to those payments (“company parity preferred securities”). As long as any company preferred securities of a UBS Preferred Funding Company remain outstanding, no company parity preferred securities may be issued by such UBS Preferred Funding Company unless the holders of at least 66²/3 % of the outstanding company preferred securities and company parity preferred securities, if any (based on the aggregate liquidation preference), voting together as a single class, approve or unless the related UBS AG subordinated guarantee is amended so that such company parity preferred securities benefit from the related UBS AG subordinated guarantee in the same manner as the company preferred securities without any adverse effect on the holders of company preferred securities. See “—Voting Rights.”

The LLC Agreement of each UBS Preferred Funding Company will preclude each UBS Preferred Funding Company from issuing, without the consent of each holder of its company preferred

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Description of Company Preferred Securities

securities, any company parity preferred securities or any other classes or series of equity securities that are senior to its company preferred securities as to dividend rights or rights upon dissolution, liquidation or winding up of such UBS Preferred Funding Company.

Dividends

General

Dividends on company preferred securities will be payable from the date of initial issuance on a noncumulative basis, regularly on the dates specified in the applicable prospectus supplement (each a “dividend payment date”) for the dividend period ending on each such dividend payment date and commencing on the date specified in the applicable prospectus supplement, but only if the relevant UBS Preferred Funding Company has legally available funds for such purpose and satisfies the other qualifications described below. Each period from and including a dividend payment date or the date of initial issuance, as applicable, to but not including the next dividend payment date is a “dividend period.”

Dividends will be payable on the liquidation preference, for each dividend period, at a fixed or floating rate, as specified in the applicable prospectus supplement.

Dividends will be mandatorily due and payable on a dividend payment date with respect to the related dividend period and special dividends will be mandatorily due and payable on other dates in the circumstances described under “—Mandatory Dividends,” except that dividends will never be mandatorily due and payable or be paid when the capital limitation (described below under “—Capital Limitation”) applies. If dividends are neither mandatorily due and payable on a dividend payment date nor prohibited by application of the capital limitation, then:

•  payment of dividends on company preferred securities will be limited by UBS AG’s available distributable profits (see “—Distributable Profits Limitation”), and

•  if UBS AG delivers, on or before the tenth business day immediately preceding a dividend payment date, an instruction (a “no dividend instruction”) to a UBS Preferred Funding Company not to pay dividends on that dividend payment date or to pay less than full dividends on that dividend payment date, dividends payable on the related dividend payment date will be limited as provided in the no dividend instruction (see “—No Dividend Instruction”).

If any dividends will be payable on company preferred securities on a day that is not a business day, those dividends will instead be paid on the next business day. No interest or other payment will be due as a result of any such adjustment.

To the extent relevant to any issuance of trust preferred securities, LIBOR shall have the meaning as specified in the applicable prospectus supplement.

All percentages resulting from any calculations on the company preferred securities will be rounded, if necessary, to the nearest one hundred-thousandth of a percentage point, with five one-millionths of a percentage point rounded upward (e.g., 9.876545% (or .09876545) being rounded to 9.87655% (or .0987655)), and all dollar amounts used in or resulting from such calculation will be rounded to the nearest cent (with one-half cent being rounded upward).

Mandatory Dividends

Each UBS Preferred Funding Company will be required to pay dividends on its company preferred securities in three circumstances, as follows:

(i)   If UBS AG declares or pays dividends or makes any other payment or distribution on any UBS AG junior obligations, and provided that the capital limitation does not apply, then each UBS Preferred Funding Company will be required to pay full dividends on its company

26

Description of Company Preferred Securities

	preferred securities during the one-year period beginning on and including the earlier of the date on which such dividend was declared or the date on which such dividend or other payment was made.
(ii)	If UBS AG or any of its subsidiaries redeems, repurchases or otherwise acquires any UBS AG parity securities or UBS AG junior obligations for any consideration, except by conversion into or exchange for shares of UBS AG or UBS AG junior obligations and except as described below (and provided that the capital limitation does not apply), then each UBS Preferred Funding Company will be required to pay dividends on its company preferred securities during the one-year period beginning on and including the date on which such redemption, repurchase or other acquisition occurred.
(iii)	If (x) UBS AG or any of its subsidiaries pays any dividends or makes any other payment or distribution on any UBS AG parity securities on any date and (y) during the relevant period (as defined below) ending on and including that date there occurred a dividend payment date as to which any UBS Preferred Funding Company paid no dividends or less than full dividends on its company preferred securities, and provided that the capital limitation does not apply, then on that date such UBS Preferred Funding Company will be required to pay a special dividend on its company preferred securities. The special dividend will be payable on that date whether or not that date is otherwise a dividend payment date and, if it is a dividend payment date, will be in addition to any other dividends required to be paid on that dividend payment date. The special dividend will be in an amount that, when taken together with dividends previously paid on the relevant company preferred securities during the relevant period, represents the same proportion of full dividends on such company preferred securities for all dividend payment dates during the relevant period that the dividend on UBS AG parity securities paid during that relevant period bears to full dividends on such UBS AG parity securities for that relevant period.

Notwithstanding paragraph (ii) above, no UBS Preferred Funding Company will be required to pay dividends solely as a result of:

•  repurchases, redemptions or other acquisitions of UBS AG parity securities or UBS AG junior obligations in connection with any employment contract, benefit plan or other similar arrangement with or for the benefit of any one or more employees, officers, directors or consultants, in connection with a dividend reinvestment or shareholder share purchase plan or in connection with the issuance of UBS AG parity securities or UBS AG junior obligations (or securities convertible into or exercisable for such UBS AG parity securities or UBS AG junior obligations) as consideration in an acquisition transaction,

•  market-making in the UBS AG parity securities or UBS AG junior obligations as part of the securities business of UBS AG or any of its subsidiaries,

•  the purchase of fractional interests in UBS AG parity securities or UBS AG junior obligations pursuant to the conversion or exchange provisions of such UBS AG parity securities or UBS AG junior obligations or the security being converted or exchanged,

•  any declaration of a dividend in connection with any shareholder’s rights plan, or the issuance of rights, shares or other property under any shareholder’s rights plan, or the redemption or repurchase of rights pursuant to any such plan, or

•  any dividend in the form of shares, warrants, options or other rights where the dividend shares or the shares issuable upon exercise of such warrants, options or other rights are the same shares as that on which the dividend is being paid or ranks equally with or junior to such shares.

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Description of Company Preferred Securities

Any dividend payment date or other date on which dividends on any company preferred securities are required to be paid as described in clause (i), (ii) or (iii) above is a “mandatory dividend payment date.” The amount of dividends required to be paid on any mandatory dividend payment date (after giving effect to the capital limitation, if applicable) is called the “mandatory dividend payment amount.” If a dividend payment date or other date is a mandatory dividend payment date, each UBS Preferred Funding Company will be required to pay the mandatory dividend payment amount as dividends on that date whether or not there are available distributable profits and whether or not interest is paid on the subordinated notes.

For purposes of this prospectus:

“UBS AG junior obligations” means (i) ordinary shares of UBS AG, (ii) each class of preferred or preference shares or similar securities of UBS AG that ranks junior to the most senior ranking preferred or preference shares or similar securities of UBS AG, and (iii) any indebtedness, guarantee or support agreement or similar undertaking of UBS AG in respect of any subsidiary securities that rank junior to the UBS AG subordinated guarantee.

“UBS AG parity securities” means (i) each class of preferred or preference shares or similar securities of UBS AG that ranks equally with the most senior ranking preferred or preference shares or similar securities of UBS AG and (ii) any securities issued by any subsidiaries of UBS AG and entitled to the benefit of any guarantee or support agreement or similar undertaking of UBS AG that ranks equally with the UBS AG subordinated guarantee. UBS AG parity securities include the USD1,500,000,000 8.622% Noncumulative Trust Preferred Securities of UBS Preferred Funding Trust I initially issued in October 2000 and representing a corresponding amount of 8.622% Noncumulative Company Preferred Securities of UBS Preferred Funding Company LLC I, guaranteed on a subordinated basis by UBS AG, the USD500,000,000 7.247% Noncumulative Trust Preferred Securities of UBS Preferred Funding Trust II issued in June 2001 and representing a corresponding amount of 7.247% Noncumulative Company Preferred Securities of UBS Preferred Funding Company LLC II, guaranteed on a subordinate basis by UBS AG, the USD300,000,000 7.25% Noncumulative Trust Preferred Securities of UBS Preferred Funding Trust III issued in June 2001 and representing a corresponding amount of 7.25% Noncumulative Company Preferred Securities of UBS Preferred Funding Company LLC III, guaranteed on a subordinate basis by UBS AG and the USD300,000,000 floating rate Noncumulative Trust Preferred Securities of UBS Preferred Funding Trust IV issued in May 2003 and representing a corresponding amount of floating rate Noncumulative Company Preferred Securities of UBS Preferred Funding Company LLC IV, guaranteed on a subordinate basis by UBS AG.

“relevant period” means (i) in the case of UBS AG parity securities that pay dividends less frequently than semi-annually, one year and (ii) in the case of UBS AG parity securities that pay dividends semi-annually or more frequently than semi-annually, six months (in each case ending on or including the date on which the related dividend on a parity security is paid but not including the corresponding day in the month that is twelve or six months prior thereto).

Capital Limitation

The prohibition on the payment of dividends on company preferred securities as described below is called the “capital limitation.”

Unless the Swiss Federal Banking Commission expressly permits otherwise, no UBS Preferred Funding Company will pay dividends on its company preferred securities on any dividend payment date (whether or not it is a mandatory dividend payment date) if on such date UBS AG is not in compliance, or because of a distribution by UBS AG or any of its subsidiaries of profits of UBS AG (including a payment of dividends on company preferred securities) would not be in compliance, with

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Description of Company Preferred Securities

the Swiss Federal Banking Commission’s minimum capital adequacy requirements applicable to UBS AG as then in effect.

For purposes of complying with the Swiss Federal Banking Commission’s capital minimum adequacy requirements, bank capital is divided into three main categories:

•  Core (or Tier 1) capital,

•  Supplementary (or Tier 2) capital, and

•  Additional (or Tier 3) capital.

Tier 1 capital primarily includes paid-in share capital, reserves (defined to include retained earnings) and capital participations of minority shareholders in fully consolidated subsidiaries, and is reduced by, among other items, the bank’s holdings of its own shares. Tier 1 capital is supplemented, for capital adequacy purposes, by Tier 2 capital, which consists of, among other things, two categories of subordinated debt instruments that may be issued by a bank, and by Tier 3 capital, which consists of certain subordinated debt obligations. The use of Tier 2 and Tier 3 capital in complying with capital ratio requirements is, however, subject to limitations.

Under Swiss law, a bank must maintain a minimum capital ratio of 8%, calculated by dividing adjusted core and supplementary capital by aggregate risk-weighted assets. This standard must be met on both a consolidated and an unconsolidated basis. UBS is required to file a statement of its required and existing capital resources, together with its annual statement of condition and interim balance sheet, with both the Swiss Federal Banking Commission and the Swiss National Bank.

For a discussion of UBS’s capital resources relative to applicable guidelines, see Item 5 of UBS AG’s Annual Report on Form 20-F for the year ended 31 December 2005, which is incorporated by reference into this prospectus.

Distributable Profits Limitation

The limitation or prohibition on the payment of dividends on company preferred securities as described below is called the “distributable profits limitation.” The distributable profits limitation will not limit or prohibit payment of mandatory dividends on a mandatory dividend payment date. The effect of the distributable profits limitation is to limit the amount of non-mandatory dividends that any UBS Preferred Funding Company may pay on its company preferred securities to the amount of dividends that UBS AG would have been legally able to pay on such securities had they been issued directly by UBS AG as non-cumulative preference shares of UBS AG.

Except as otherwise stated in the applicable prospectus supplement, on or before the first dividend payment date of each year, UBS AG will deliver a certificate to each UBS Preferred Funding Company (a “distributable profits limitation certificate”) specifying:

•  the distributable profits (as defined below) of UBS AG for the financial year ending on the preceding 31 December, and

•  the available distributable profits (as defined below) for payment of dividends on company preferred securities on the dividend payment dates in the then current year.

Unless a UBS Preferred Funding Company is required to pay mandatory dividends:

•  the aggregate amount of dividends on company preferred securities that such UBS Preferred Funding Company may pay on the first dividend payment of the current year may not exceed the lesser of full dividends and the available distributable profits set forth in such distributable profits limitation certificate, and

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Description of Company Preferred Securities

•  the aggregate amount of dividends on company preferred securities that such UBS Preferred Funding Company may pay on any subsequent dividend payment date in the current year may not exceed the lesser of full dividends and the remaining amount of such available distributable profits (after giving effect to the payment of dividends pursuant to this bullet point or the bullet point immediately above).

For purposes of this prospectus:

“distributable profits” means, for any financial year of UBS AG, profit that may be distributed in accordance with Swiss law then applicable. Currently, for any financial year of UBS AG, distributable profits are equal to profit brought forward, plus profit for the period, minus appropriation to general statutory reserve, plus other reserves, each as shown in the audited unconsolidated balance sheet and statement of appropriation of retained earnings of UBS AG and as determined in accordance with accounting standards applicable under Swiss law. The “appropriation to general statutory reserve” is equal to up to 5% of annual profit to the extent the general reserves of UBS AG do not equal 20% of the paid-in share capital plus 10% of the amount distributed as a dividend from profit for the period in excess of 5% of the par value of the UBS common shares. UBS AG’s distributable profits for 2005 were approximately CHF 26.792 billion.

“available distributable profits” means, for any financial year of UBS AG:

•  if there are no UBS AG parity securities outstanding, distributable profits for the immediately preceding financial year of UBS AG, and

•  if there are UBS AG parity securities outstanding, then an amount determined as the product of:

(x)   distributable profits for the immediately preceding financial year of UBS AG, and

(y)  a ratio (I) the numerator of which is the aggregate amount of full dividends on the company preferred securities to be paid on the dividend payment dates that occur during the then current financial year (not including dividends paid in any preceding dividend payment date during of the current year and including dividends to be paid in the corresponding dividend payment date of the following year) and (II) the denominator of which is equal to the amount determined pursuant to clause (I) plus the aggregate amount of full dividends on the UBS AG parity securities to be paid on dividend payment dates which occur during the then current financial year.

No Dividend Instruction

Except for the mandatory dividend payment amounts required to be paid on mandatory dividend payment dates:

•  dividends on company preferred securities will not be payable on a dividend payment date if, on or before the tenth business day immediately preceding such dividend payment date, UBS AG delivers a no dividend instruction to the relevant UBS Preferred Funding Company instructing it not to pay dividends on that dividend payment date, and

•  if, on or before the tenth business day immediately preceding such dividend payment date, UBS AG delivers a no dividend instruction to a UBS Preferred Funding Company limiting but not prohibiting the payment of dividends on such dividend payment date, dividends on such UBS Preferred Funding Company’s company preferred securities will be payable on that dividend payment date only to the extent permitted by such no dividend instruction.

If a no dividend instruction is given to a UBS Preferred Funding Company, then such UBS Preferred Funding Company must promptly give notice to the holders of its company preferred securities in the

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Description of Company Preferred Securities

manner described under “—Notices” of the fact that it has received a no dividend instruction and the amount of dividends, if any, that will be paid on the related dividend payment date.

Additional Amounts

If any UBS Preferred Funding Company or UBS Preferred Funding Trust is required to withhold any taxes, duties or other governmental charges with respect to any dividend payment on its trust preferred securities or company preferred securities, the relevant UBS Preferred Funding Company will be required to pay, as additional amounts included in the dividend payment (and UBS AG will be required to include in any related payment made by it under the UBS AG subordinated guarantee), an amount sufficient that the net amount received by the holder of such company preferred securities or trust preferred securities, as applicable, after the withholding, will not be less than the dividend payment amount. However, no UBS Preferred Funding Company will be required to pay any such additional amounts to the extent that the taxes, duties or other governmental charges are imposed or levied by Switzerland or the Cayman Islands because the holder or beneficial owner of any trust preferred securities or company preferred securities:

•  has some connection with Switzerland or the Cayman Islands, as applicable, other than being a holder or beneficial owner of those trust preferred securities or company preferred securities, or

•  has not made a declaration of non-residence in, or other lack of connection with, Switzerland or the Cayman Islands, as applicable, or any similar claim for exemption, if the relevant UBS Preferred Funding Company has given the beneficial owner of those trust preferred securities or company preferred securities or its nominee at least 60 days’ prior notice of an opportunity to make the declaration or claim.

Ranking and Liquidation Preference

The company preferred securities of any UBS Preferred Funding Company ordinarily will rank senior to its company common securities as to the payment of dividends. However, UBS AG has the right to shift the dividend preference of company preferred securities to the company common securities on any dividend payment date to the extent that the mandatory dividend payment amount then required to be paid as dividends on the company preferred securities (if any) is less than full dividends on the company preferred securities. If UBS AG shifts the dividend preference to the company common securities, the interest payment received by a UBS Preferred Funding Company on the related subordinated notes will be returned as dividends to UBS AG, as the holder of its company common securities, before any dividends are paid on its company preferred securities.

As long as any company preferred securities of a UBS Preferred Funding Company are outstanding, UBS AG will agree in such UBS Preferred Funding Company’s LLC Agreement that it will take no voluntary action to cause the UBS Preferred Funding Company to dissolve or liquidate unless UBS AG also liquidates. Each UBS Preferred Funding Company’s LLC Agreement will provide that the UBS Preferred Funding Company will be liquidated if UBS AG is liquidated.

If any UBS Preferred Funding Company dissolves, liquidates or winds up, then after the claims of any creditors of such UBS Preferred Funding Company are satisfied, the holders of its company preferred securities will be entitled to receive, before any distribution of assets is made to the holders of its company common securities or any other class of shares ranking junior to the company preferred

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Description of Company Preferred Securities

securities upon liquidation, liquidating distributions in respect of such company preferred securities in the amount of:

•  the liquidation preference of the company preferred securities, plus

•  an amount equal to unpaid dividends, if any, on the company preferred securities with respect to the current dividend period accrued on a daily basis to the date of liquidation, plus

•  an amount equal to unpaid definitive dividends for any prior dividend period, without interest and without accumulation of unpaid nondefinitive dividends for any prior dividend period.

For purposes of this prospectus:

“definitive dividends” means, as to a dividend payment date and related dividend period, dividends that are due and payable because (i) they are not limited by the capital limitation and (ii) either (x) they are mandatory dividends or (y) a no dividend instruction was not delivered and they are not limited by the distributable profit limitation.

“nondefinitive dividends” means, as to a dividend payment date and related dividend period, dividends that are not definitive dividends.

If UBS AG is liquidated, whether voluntarily or involuntarily, (i) each UBS Preferred Funding Company will be liquidated and (ii) under each UBS AG Subordinated Guarantee Agreement, the holders of related company preferred securities (whether through a UBS Preferred Funding Trust or as direct holders who have withdrawn their company preferred securities from a UBS Preferred Funding Trust) will have a claim entitling them to substantially the same liquidating distributions in the liquidation of UBS AG that they would have been entitled to if they had purchased preferred shares of UBS AG having an aggregate liquidation preference equal to the aggregate liquidation preference of their company preferred securities and bearing dividends at the rate of dividends applicable to such company preferred securities. Each UBS AG Subordinated Guarantee Agreement and the related UBS Preferred Funding Company’s LLC Agreement, taken together, provide that the holders of company preferred securities may not receive liquidating distributions in a liquidation of the relevant UBS Preferred Funding Company and payments under the UBS AG subordinated guarantee that, taken together, exceed the liquidating distributions to which they would have been entitled had they instead owned preferred shares of UBS AG with equivalent terms as described above.

Voting Rights

Except as expressly required by applicable law, or except as indicated below, the holders of company preferred securities will not be entitled to vote. Unless otherwise specified in the applicable prospectus supplement, if the holders of company preferred securities of any UBS Preferred Funding Company are entitled to vote as indicated below, each USD25 or USD1000, as the case may be, liquidation preference of company preferred securities will be entitled to one vote on matters on which the holders of such company preferred securities are entitled to vote. If at any time the aggregate of unpaid dividends for any UBS Preferred Funding Company equals or exceeds the number of regularly scheduled dividend payments, specified in the applicable prospectus supplement, the holders of company preferred securities and any company parity preferred securities of such UBS Preferred Funding Company, voting together as a single class, will have the exclusive right to elect two additional directors of their choosing. Holders of a majority (based on the aggregate liquidation preference) of company preferred securities and any company parity preferred securities of such UBS Preferred Funding Company may exercise this right by written consent or at a meeting of such holders called for such purpose. This right will continue either until all unpaid dividends have been paid in full or until full dividends have been paid on the relevant company preferred securities for the number of consecutive dividend periods specified in the prospectus supplement. While this right continues, any

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Description of Company Preferred Securities

vacancy in the office of the additional directors may be filled only by the holders of company preferred securities and company parity preferred securities voting as described above.

Each UBS Preferred Funding Company’s LLC Agreement will provide that a meeting will be called at the request of holders of 25% (based on the aggregate liquidation preference) of its company preferred securities and any company parity preferred securities.

As long as any of its company preferred securities are outstanding, no UBS Preferred Funding Company may, without the consent or vote of holders of at least 66²/3 % of its outstanding company preferred securities and company parity preferred securities, if any (based on the aggregate liquidation preference), voting together as a single class:

•  change or remove any provision of such UBS Preferred Funding Company’s LLC Agreement (including the terms of its company preferred securities), issue any company parity preferred securities, redeem or repurchase any company common securities, or consent to a change in the booking location of the issuance of the related subordinated notes to a branch or other office of UBS AG other than the Cayman Islands branch of UBS AG, in each case, if such action would materially and adversely affect the rights, preferences, powers or privileges of its company preferred securities and such company parity preferred securities,

•  to the fullest extent permitted by law, liquidate, dissolve or terminate such UBS Preferred Funding Company without the concurrent liquidation of UBS AG,

•  amend or modify such UBS Preferred Funding Company’s investment policies, or

•  merge, convert, consolidate, reorganize or effect any other business combination involving such UBS Preferred Funding Company, unless the resulting entity will have no class or series of equity securities either authorized or outstanding that ranks ahead of its company preferred securities as to dividends or as to the distribution of assets upon liquidation, dissolution or winding up, except the same number of shares of such equity securities with the same preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications or terms or conditions or redemption as the shares of equity securities of such UBS Preferred Funding Company that are authorized and outstanding immediately prior to such transaction, and each holder of its company preferred securities immediately prior to such transaction shall receive securities with the same preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications or terms or conditions or redemption of the resulting entity as the company preferred securities held by such holder immediately prior to the transaction.

As long as any of its company preferred securities are outstanding, no UBS Preferred Funding Company will be permitted, without the consent of the holders of each outstanding company preferred security, authorize, create or increase the authorized amount of, or issue any class or series of, any equity securities of such UBS Preferred Funding Company, or any warrants, options or other rights convertible or exchangeable into any class or series of any equity securities of such UBS Preferred Funding Company, ranking prior to its company preferred securities, either as to dividend rights or rights on dissolution, liquidation or winding up of such UBS Preferred Funding Company.

Notwithstanding any of the foregoing, without consent of any holder of company preferred securities, UBS AG will be permitted to amend or supplement the UBS AG Subordinated Guarantee Agreements to correct or supplement any provision in the UBS AG Subordinated Guarantee Agreements which may be defective or inconsistent with any other provision therein, or to make any other provisions with respect to matters or questions arising under the UBS AG Subordinated Guarantee Agreements, so long as any such action shall not materially adversely affect the interests of the holders of the related company preferred securities. See “Description of UBS AG Subordinated Guarantees—Amendments.”

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Description of Company Preferred Securities

Notwithstanding the foregoing, without the consent of any holder of company preferred securities, UBS AG will be permitted to amend or supplement any UBS Preferred Funding Company’s LLC Agreement:

•  to correct or supplement any provision in a UBS Preferred Funding Company’s LLC Agreement which may be defective or inconsistent with any other provision therein, or to make any other provisions with respect to matters or questions arising under a UBS Preferred Funding Company’s LLC Agreement, so long as any such action shall not materially adversely affect the interests of the holders of company preferred securities of such UBS Preferred Funding Company, or

•  to cure any ambiguity or correct any mistake.

Redemption

No company preferred securities will be redeemable before the date specified in the applicable prospectus supplement unless a Tax Event, an Investment Company Act Event or a Capital Event occurs, in which case each UBS Preferred Funding Company may redeem its company preferred securities in whole (but not in part) at any time on not less than 30 nor more than 60 days’ notice. On or after the date specified in the applicable prospectus supplement, any UBS Preferred Funding Company will be permitted to redeem its company preferred securities for cash, in whole or in part, on not less than 30 nor more than 60 days’ notice.

Unless otherwise stated in the applicable prospectus supplement, the redemption price for such optional redemptions on or after the date specified in the applicable prospectus supplement and for redemptions arising from a Tax Event, an Investment Company Act Event or a Capital Event will be:

•  100% of the liquidation preference of the company preferred securities being redeemed, plus

•  an amount equal to unpaid dividends, if any, on the company preferred securities with respect to the current dividend period (whether or not declared) accrued on a daily basis to the date fixed for redemption, plus

•  an amount equal to unpaid definitive dividends for any prior dividend period, without interest and without accumulation of unpaid nondefinitive dividends for any prior dividend period.

The applicable prospectus supplement may provide that the redemption price for a redemption arising out of a Tax Event resulting from a Change in Tax Law (as defined below) and relating to the:

•  imposition of tax on UBS Preferred Funding Trust or UBS Funding Company, or

•  the imposition of withholding tax on UBS Preferred Funding Company’s payment of dividends on the company preferred securities, on UBS Preferred Funding Trust’s payment of dividends on the trust preferred securities, on UBS AG’s payment of interest on the subordinated notes or on UBS AG’s payment under the subordinated guarantee

(which are the events described in clauses (A), (B) and (C) of the definition of “Tax Event”) will be the redemption price described above and that the redemption price for all other redemptions arising out of a Tax Event resulting from a Change in Tax Law will be:

•  the Make Whole Amount (as defined below), plus

•  an amount equal to unpaid dividends, if any, on the company preferred securities with respect to the current dividend period (whether or not declared) accrued on a daily basis to the date fixed for redemption, plus

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Description of Company Preferred Securities

•  an amount equal to unpaid definitive dividends for any prior dividend period, without interest and without accumulation of unpaid nondefinitive dividends for any prior dividend period.

To the extent provided for in the applicable prospectus supplement, UBS Preferred Funding Company will have, until the dividend payment date specified in the applicable prospectus supplement after the occurrence of a Tax Event, an Investment Company Act Event or a Capital Event, the right to redeem the company preferred securities.

Any redemption of company preferred securities will have to comply with applicable regulatory requirements, including the prior approval of the Swiss Federal Banking Commission if then required under applicable guidelines or policies of the Swiss Federal Banking Commission. The Swiss Federal Banking Commission in its discretion may impose conditions on its approval of any proposed redemption of company preferred securities. If dividends on any company preferred securities of a UBS Preferred Funding Company are unpaid, no company preferred securities of such UBS Preferred Funding Company may be redeemed unless all its outstanding company preferred securities are redeemed, and no UBS Preferred Funding Company may purchase or otherwise acquire any of its company preferred securities, except pursuant to a purchase or exchange offer made on the same terms to the holders of all of its outstanding company preferred securities.

Company preferred securities will not be subject to any sinking fund or mandatory redemption and will not be convertible into any other securities of the relevant UBS Preferred Funding Company or any securities of UBS AG.

“Change in Tax Law” means the receipt by UBS AG of an opinion of a nationally recognized law firm or other tax advisor (which may be an accounting firm) in Switzerland, the United States or the Cayman Islands, as appropriate, experienced in such matters to the effect that an event of the type descried in clause (A), (B) or (C) of the definition of “Tax Event” has occurred or will occur as a result of (i) any amendment to, clarification of, or change (including any announced prospective change) in, the laws or treaties (or any regulations under any laws or treaties) of the United States, Switzerland or the Cayman Islands or any political subdivision or taxing authority of or in the United States, Switzerland or the Cayman Islands affecting taxation or (ii) any administrative action or any amendment to, clarification of, or change in the official position of or UBS AG interpretation of any administrative action or any interpretation or pronouncement that provides for a position with respect to any administrative action or any interpretation or pronouncement that provides for a position with respect to any administrative action that differs from the previously generally accepted position, in each case, by any legislative body, court, governmental authority or regulatory body, regardless of the manner in which such amendment, clarification, change, interpretation or pronouncement is made known, which amendment, clarification, change or administrative action is effective or which interpretation or pronouncement is announced on or after the date of issuance of the company preferred securities.

“Make Whole Amount” as applied to a redemption of the company preferred securities means the greater of (i) 100% of the liquidation preference of the company preferred securities and (ii) as determined by a quotation agent (as defined below), the sum of the present value of the liquidation preference of the company preferred securities together with the present values of scheduled payments of dividends accrued from the date of redemption to the dividend payment date specified in the applicable prospectus supplement (the “remaining life”), in each case discounted to the date of redemption on a semi-annual basis (assuming a 360-day consisting of twelve 30-day months) at the adjusted treasury rate.

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Description of Company Preferred Securities

For purposes of determining the Make Whole Amount:

“adjusted treasury rate” means, with respect to any redemption date, the treasury rate plus a spread as described in the applicable prospectus supplement.

As long as any company preferred securities of a UBS Preferred Funding Company are outstanding, other company parity preferred securities of such UBS Preferred Funding Company may not be redeemed or repurchased unless such UBS Preferred Funding Company concurrently redeems an approximately equal proportion of the aggregate liquidation preference of its outstanding company preferred securities or each rating agency then rating its company preferred securities informs such UBS Preferred Funding Company in writing that the redemption or repurchase of such company parity preferred securities would not result in a reduction or withdrawal of the rating then assigned by that rating agency to its company preferred securities.

If fewer than all outstanding company preferred securities of a UBS Preferred Funding Company are to be redeemed, the amount of the company preferred securities of such UBS Preferred Funding Company to be redeemed will be determined by the board of directors of such UBS Preferred Funding Company, and the securities to be redeemed will be determined by lot or pro rata as the board of directors in its sole discretion determines to be equitable. The relevant UBS Preferred Funding Company will promptly notify the registrar and transfer agent for its company preferred securities in writing of the securities selected for redemption and, in the case of any partial redemption, the liquidation preference to be redeemed.

Any company preferred securities redeemed will be canceled. There will be no prescription period in respect of uncollected dividends on company preferred securities.

As used in this prospectus:

“Administrative action” means any judicial decision, official administrative pronouncement, published or private ruling, regulatory procedure, notice or announcement (including any notice or announcement of intent to adopt such procedures or regulations) by any legislative body, court, governmental authority or regulatory body having appropriate jurisdiction.

“Capital Event” means, with respect to any UBS Preferred Funding Company, the determination by UBS AG after consultation with the Swiss Federal Banking Commission that its company preferred securities cannot be included in calculating the Tier 1 capital of UBS AG on a consolidated basis.

“Comparable Treasury Issue” means with respect to any redemption date the United States Treasury security selected by the quotation agent as having a maturity comparable to the remaining life that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining life. If no United States Treasury security has a maturity that is within a period from three months before to three months after the interest payment date and dividend payment date specified in the applicable prospectus supplement, the two most closely corresponding United States Treasury securities will be used as the comparable treasury issue, and the treasury rate will be interpolated or extrapolated on a straight-line basis, rounding to the nearest month using such securities.

“Comparable Treasury Price” means (A) the average of five reference treasury dealer quotations for such redemption date, after excluding the highest and lowest of such reference treasury dealer quotations, or (B) if the quotation agent obtains fewer than five such reference treasury dealer quotations, the average of all such quotations.

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Description of Company Preferred Securities

“quotation agent” means UBS Securities LLC and its successors, except that if UBS Securities LLC ceases to be primary U.S. Government securities dealer in New York City (a “primary treasury dealer”), UBS Preferred Funding Company will designate another primary treasury dealer.

“Reference Treasury Dealer” means (i) the quotation agent and (ii) any other primary treasury dealer selected by the quotation agent after consultation with the relevant UBS Preferred Funding Company.

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

“Treasury Rate” means (i) the yield, under the heading which represents the average for the week immediately prior to the redemption date, appearing in the most recently published statistical release designated “H.15(519)” or any successor publication which is published weekly by the Federal Reserve and which established yields on actively traded United States Treasury securities adjusted to constant maturity under the caption “Treasury Constant Maturities,” for the maturity corresponding to the remaining life (or, if no maturity is within three months before or after the remaining life, yields for the two published maturities most closely corresponding to the remaining life will be determined and the treasury rate will be interpolated or extrapolated from such yields on a straight-line basis, rounding to the nearest month) or (ii) if such release (or any successor release) is not published during the week preceding the calculation date or does not contain such yields, the rate per annum equal to the semi-annual equivalent yield to maturity of the comparable treasury issue, calculated using a price for the comparable treasury issue (expressed as a percentage of its principal amount) equal to the comparable treasury price for such redemption date. The treasury rate will be calculated on the third business day preceding the redemption date.

“Investment Company Act Event” means, with respect to any UBS Preferred Funding Company, the receipt by UBS AG of an opinion of a nationally recognized law firm in the United States experienced in such matters to the effect that there is more than an insubstantial risk that such UBS Preferred Funding Company or the related UBS Preferred Funding Trust is an “investment company” within the meaning of the Investment Company Act of 1940.

“Tax Event” means, with respect to any UBS Preferred Funding Company, the receipt by UBS AG of an opinion of a nationally recognized law firm or other tax advisor (which may be an accounting firm) in Switzerland or the United States, as appropriate, experienced in such matters to the effect that there is more than an insubstantial risk that (A) such UBS Preferred Funding Company or the related UBS Preferred Funding Trust is or will be subject to more than a de minimis amount of additional taxes, duties or other governmental charges, (B) UBS AG is or will be required to pay any additional amounts in respect of any taxes, duties or other governmental charges with respect to payments of interest or principal on the related subordinated notes and with respect to any payments on the related trust preferred securities, (C) such UBS Preferred Funding Company is or will be required to pay any additional amounts in respect of any taxes, duties or other governmental charges with respect to payments of dividends on its company preferred securities or the related UBS Preferred Funding Trust is or will be required to pay any additional amounts in respect of any taxes, duties or other governmental charges with respect to distributions on its trust preferred securities, or (D) the treatment of any of such UBS Preferred Funding Company’s items of income, gain, loss, deduction or expense, or the treatment of any item of income, gain, loss, deduction or expense of UBS AG related to the related subordinated notes or its ownership of such UBS Preferred Funding Company, in each case as reflected on the

37

Description of Company Preferred Securities

tax returns (including estimated returns) filed (or to be filed) by such UBS Preferred Funding Company or UBS AG, will not be respected by a taxing authority, as a result of which such UBS Preferred Funding Company or UBS AG is or will be subject to more than a de minimis amount of additional taxes, duties or other governmental charges or civil liabilities, the effect of which cannot be avoided by such UBS Preferred Funding Company or UBS AG taking reasonable measures available to it without any adverse effect on or material cost to UBS AG or such UBS Preferred Funding Company (as determined by UBS AG in its sole discretion).

Registrar and Transfer Agent

Wilmington Trust Company, or any other entity that UBS AG designates, will act as registrar and transfer agent for the company preferred securities.

Registration of transfers of company preferred securities will be effected without charge by or on behalf of the relevant UBS Preferred Funding Company, but upon payment of any tax or other governmental charges that may be imposed in connection with any transfer or exchange. No UBS Preferred Funding Company will be required to register or cause to be registered the transfer of its company preferred securities after such company preferred securities have been called for redemption.

The LLC Agreement of each UBS Preferred Funding Company will provide that, in the event of a partial redemption of its company preferred securities that would result in a delisting of the related trust preferred securities from any securities exchange on which such trust preferred securities are then listed, such UBS Preferred Funding Company will redeem its company preferred securities in whole.

Notices

Notices to the holders of company preferred securities will be mailed by first-class mail, postage prepaid, to the holders’ addresses appearing in the relevant UBS Preferred Funding Company’s records.

Governing Law

The LLC Agreement of each UBS Preferred Funding Company and the company preferred securities are governed by the laws of the State of Delaware.

Nature of the Trading Market

The company preferred securities will not be listed on any national exchange or traded in any established market.

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Book-Entry Issuance of Trust Preferred Securities

The trust preferred securities will initially be issued to investors only in book-entry form. The total aggregate amount of trust preferred securities of each UBS Preferred Funding Trust will be represented by permanent global securities in fully registered form (each, a “global certificate”) and deposited with a custodian for, and registered in the name of The Depository Trust Company (“DTC”) or its nominee. Except as provided in the applicable prospectus supplement, the global certificates will initially be deposited with Wilmington Trust Company, as the custodian for DTC, and registered in the name of Cede & Co., as the nominee of DTC.

Except as described below, the global certificates may be transferred, in whole and not in part, only to another nominee of DTC or a successor of DTC or its nominee. Beneficial interests in the global certificates may not be exchanged for trust preferred securities in certificated form except in the limited circumstances described below.

Persons that acquire beneficial ownership interests in any global certificate will hold their interests through either (i) DTC in the United States or (ii) Clearstream Banking or the Euroclear System in Europe if such persons are participants in those systems, or indirectly through organizations that are participants in those systems. Clearstream and Euroclear will hold omnibus positions on behalf of their participants through customers’ securities accounts in Clearstream’s and Euroclear’s names on the books of their respective depositaries, which in turn will hold those positions in customers’ securities accounts in the depositaries’ names on the books of DTC. Unless and until certificated securities are issued, the only “holder” of any trust preferred securities will be Cede & Co., as nominee of DTC, or the nominee of a successor depositary. Beneficial owners will be permitted to exercise their rights only indirectly through DTC, Clearstream, Euroclear and their participants.

Withdrawal of Related Company Preferred Securities Represented by Trust Preferred Securities

Any beneficial owner of trust preferred securities may withdraw and hold directly a corresponding amount of related company preferred securities as described under “Description of Trust Preferred Securities—Withdrawal of Company Preferred Securities.” Within a reasonable period after such request has been properly made, the trustee of the relevant UBS Preferred Funding Trust will instruct DTC to reduce the number of trust preferred securities represented by the relevant global certificate by the amount of related company preferred securities to be so withdrawn by the withdrawing owner.

Company preferred securities that are withdrawn will be issued only in definitive, fully-registered form and will not be eligible to be held through DTC, Euroclear or Clearstream, and under current law the holders of such company preferred securities will receive an annual Form K-1 instead of the Form 1099 that is received by the holders of trust preferred securities. See “U.S. Tax Considerations— Information Reporting and Backup Withholding Tax.”

Any holder of company preferred securities may redeposit its company preferred securities as described under “Description of Trust Preferred Securities—Withdrawal of Company Preferred Securities.” Within a reasonable period after such deposit is properly made, the trustee of the relevant UBS Preferred Funding Trust will instruct DTC to increase the number of trust preferred securities represented by the relevant global certificate accordingly.

The Depository Trust Company

The Depository Trust Company, or 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

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Book-Entry Issuance of Trust Preferred Securities

member of the Federal Reserve System, a “clearing corporation” within the meaning of the New York Uniform Commercial Code, and a “clearing agency” registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934.

DTC holds securities that its participants deposit with DTC. DTC also facilitates the settlement among its participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in its participants’ accounts, eliminating the need for physical movement of securities certificates. Participants in DTC include Clearstream and Euroclear, securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations.

DTC is owned by a number of its participants and by the New York Stock Exchange, the American Stock Exchange, Inc. and the National Association of Securities Dealers, Inc. Access to DTC 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 DTC participant, either directly or indirectly. The rules applicable to DTC and its participants are on file with the SEC.

Clearstream Banking

Clearstream Banking, société anonyme, or Clearstream, is incorporated under the laws of Luxembourg as a professional depositary. Clearstream holds securities for its participating organizations and facilitates the clearance and settlement of securities transactions between its participants through electronic book-entry changes in accounts of its participants, eliminating the need for physical movement of certificates. Transactions may be settled in Clearstream in any of 28 currencies, including U.S. dollars.

Clearstream provides to its participants, among other things, services for safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic markets in several countries. As a professional depositary, Clearstream is subject to regulation by the Luxembourg Monetary Institute. Clearstream participants are recognized financial institutions around the world, including securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations. Indirect access to Clearstream is also available to others, such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a Clearstream participant, either directly or indirectly.

Euroclear System

Euroclear was created in 1968 to hold securities for its participants and to clear and settle transactions between its participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. The Euroclear System is owned by Euroclear Clearance System Public Limited Company (ECS plc) and operated through a license agreement by Euroclear Bank S.A./N.V., a bank incorporated under the laws of the Kingdom of Belgium (the “Euroclear Operator”).

The Euroclear Operator holds securities and book-entry interests in securities for participating organizations and facilitates the clearance and settlement of securities transactions between Euroclear participants, and between Euroclear participants and participants of certain other securities intermediaries through electronic book-entry changes in accounts of such participants or other securities intermediaries.

The Euroclear Operator provides Euroclear participants, among other things, with safekeeping, administration, clearance and settlement, securities lending and borrowing, and related services.

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Book-Entry Issuance of Trust Preferred Securities

Non-participants of Euroclear may hold and transfer book-entry interests in the securities through accounts with a direct participant of Euroclear or any other securities intermediary that holds a book-entry interest in the securities through one or more securities intermediaries standing between such other securities intermediary and Euroclear Operator.

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

Participants and Beneficial Owners

Purchases of trust preferred securities within the DTC system must be made by or through DTC participants, which will receive a credit for the trust preferred securities on DTC’s records and on the records of Clearstream or Euroclear, if applicable. The ownership interest of each actual purchaser of trust preferred securities, which is that of a beneficial owner of an interest in a global certificate, is in turn to be recorded on the DTC participants’ and indirect participants’ records.

Beneficial owners of interests in a global certificate will not receive written confirmation from DTC of their purchases, but beneficial owners of an interest in a global certificate are expected to receive written confirmations providing details of the transactions, as well as periodic statements of their holdings, from the DTC participants or indirect participants through which the beneficial owners of an interest in a global certificate purchased their ownership interests in the relevant trust preferred securities. Transfers of ownership interests in trust preferred securities will be accomplished by entries made on the books of DTC participants and indirect participants acting on behalf of beneficial owners of an interest in a global certificate. Beneficial owners of interests in a global certificate will not receive certificates representing their ownership interests in the relevant trust preferred securities, unless use of the book-entry system for such trust preferred securities is discontinued.

Transfers Among DTC, Clearstream and Euroclear

Transfers between DTC participants will occur in accordance with the rules of DTC. Transfers between Clearstream and Euroclear participants will occur in accordance with their respective rules and operating procedures.

Cross-market transfers between persons holding directly or indirectly through DTC, on the one hand, and directly or indirectly through Clearstream or Euroclear participants, on the other, will be effected in DTC in accordance with the rules of DTC on behalf of the relevant European international clearing system by the relevant European depositary. However, those cross-market transactions will require delivery of instructions to the relevant European international clearing system by the counterparty in that system in accordance with its rules and procedures and within its established deadlines, European time. The relevant European international clearing system will, if the transaction meets its settlement requirements, deliver instructions to the relevant European depositary to take action to effect final settlement on its behalf by delivering or receiving securities in DTC, and making or receiving payment in accordance with normal procedures for same-day funds settlement applicable to DTC. Clearstream and Euroclear participants may not deliver instructions directly to the European depositaries.

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Book-Entry Issuance of Trust Preferred Securities

Because of time zone differences, credits of trust preferred securities received in Clearstream or Euroclear as a result of a transaction with a person that does not hold trust preferred securities through Clearstream or Euroclear will be made during subsequent securities settlement processing and dated the business day following the DTC settlement date. Those credits or any transactions in those securities settled during that processing will be reported to the relevant Euroclear or Clearstream participants on that business day. Cash received in Clearstream or Euroclear as a result of sales of trust preferred securities by or through a Clearstream or Euroclear participant to a DTC participant will be received with value on the DTC settlement date, but will be available in the relevant Clearstream or Euroclear cash account only as of the business day following settlement in DTC.

Limitations on Responsibilities of DTC, Clearstream and Euroclear

DTC, Clearstream and Euroclear have no knowledge of the actual beneficial owners of interests in a global certificate representing trust preferred securities. DTC’s records reflect only the identity of the DTC participants, including Clearstream and Euroclear, to whose accounts those trust preferred securities are credited, which may or may not be the beneficial owners of interests in a global certificate. Similarly, the records of Clearstream and Euroclear reflect only the identity of the Clearstream or Euroclear participants to whose accounts those trust preferred securities are credited, which also may or may not be the beneficial owners of interests in a global certificate. DTC, Clearstream and Euroclear participants and indirect participants will remain responsible for keeping account of their holdings on behalf of their customers.

DTC’s Procedures for Notices, Voting and Payments

So long as DTC, or its nominee, is the registered owner or holder of a global certificate, DTC or that nominee, as the case may be, will be considered the sole owner or holder of trust preferred securities represented by the global certificate for all purposes under the relevant Amended and Restated Trust Agreement. No beneficial owner of an interest in a global certificate will be able to transfer that interest except in accordance with DTC’s applicable procedures, in addition to those provided for under the relevant Amended and Restated Trust Agreement.

DTC has advised UBS AG, as provider of the UBS AG subordinated guarantees, that it will take any action permitted to be taken by a holder of relevant trust preferred securities, including the presentation of trust preferred securities for exchange as described below, only at the direction of one or more of its participants to whose account the DTC interests in the global certificates are credited and only in respect of that portion of the aggregate liquidation amount of trust preferred securities as to which that participant or participants has or have given the direction.

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

The relevant trustee will send redemption notices in respect of trust preferred securities held in book-entry form to Cede & Co., and will also give those notices in the manner indicated under “Description of Trust Preferred Securities— Notices.” If less than all the trust preferred securities of any UBS Preferred Funding Trust are being redeemed, DTC will determine the amount of the interest of each DTC participant to be redeemed in accordance with its procedures.

Although voting with respect to trust preferred securities is limited, in those cases where a vote is required, neither DTC nor Cede & Co. will itself consent or vote with respect to such trust preferred securities. Under its usual procedures, DTC will mail an Omnibus Proxy to the relevant UBS Preferred Funding Trust as soon as possible after the record date. The Omnibus Proxy assigns Cede & Co.’s

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Book-Entry Issuance of Trust Preferred Securities

consenting or voting rights of those participants to whose accounts such trust preferred securities are allocated on the record date identified in a listing attached to the Omnibus Proxy.

Distributions on trust preferred securities held in book-entry form will be made to DTC in immediately available funds. DTC’s practice is to credit its participants’ accounts on the relevant payment date in accordance with their respective holdings shown on DTC’s records unless DTC has reason to believe that it will not receive payments on that payment date. Payments by DTC’s participants and indirect participants to beneficial owners of interests in a global certificate will be governed by standing instructions and customary practices. Such payments will be the responsibility of those participants and indirect participants and not of DTC, the relevant UBS Preferred Funding Trust or UBS AG, as the guarantor, subject to any statutory or regulatory requirements that may be in effect from time to time. Payment of any dividends or other amounts to DTC is the responsibility of the relevant UBS Preferred Funding Trust, disbursement of such payments to participants is the responsibility of DTC, and disbursement of those payments to the beneficial owner of an interest in a global certificate is the responsibility of participants and indirect participants.

Except as described in this prospectus, a beneficial owner of an interest in a global certificate will not be entitled to receive physical delivery of the trust preferred securities. Accordingly, each beneficial owner of an interest in a global certificate must rely on the procedures of DTC to exercise any rights under its trust preferred securities.

Termination of and Changes to Depositary Arrangements

A global certificate is exchangeable for trust preferred securities in registered certificated form if DTC:

•  notifies the relevant UBS Preferred Funding Trust that it is unwilling or unable to continue as depositary for the global certificates and such UBS Preferred Funding Trust does not appoint a successor depositary, or

•  has ceased to be a clearing agency registered under the Securities Exchange Act of 1934.

Although DTC, Clearstream and Euroclear have agreed to the foregoing procedures in order to facilitate transfers of interests in the global certificates among participants, none is under any obligation to perform or continue to perform those procedures, and those procedures may be discontinued at any time. Neither UBS AG nor any UBS Preferred Funding Trust will have any responsibility for the performance by DTC, Clearstream, Euroclear or their participants or indirect participants under the rules and procedures governing them. DTC, Clearstream or Euroclear may discontinue providing its services as securities depositary with respect to any trust preferred securities at any time by giving notice to the relevant UBS Preferred Funding Trust. Under those circumstances, definitive trust preferred security certificates with respect to such trust preferred securities would be delivered as described under “Description of Trust Preferred Securities— Transfer and Issue of Definitive Trust Preferred Securities.”

Limitations on Rights Resulting from Book-Entry Form

The laws of some jurisdictions require that certain purchasers of securities take physical delivery of securities in definitive form. These laws may impair the ability to transfer beneficial interests in the global trust preferred securities as represented by a global certificate.

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Description of UBS AG Subordinated Guarantees

At or prior to the issuance of any trust preferred securities and the related company preferred securities, UBS AG and Wilmington Trust Company, as guarantee trustee, will execute the related UBS AG Subordinated Guarantee Agreements. We will qualify the UBS AG Subordinated Guarantee Agreements as indentures under the Trust Indenture Act. The terms of the UBS AG subordinated guarantees will include both those stated in the UBS AG Subordinated Guarantee Agreements and those made part of the UBS AG Subordinated Guarantee Agreements by the Trust Indenture Act. The following summary of the material terms and provisions of the UBS AG subordinated guarantees is not complete and is subject to, and qualified in its entirety by reference to, the UBS AG Subordinated Guarantee Agreements and the Trust Indenture Act. We have filed a copy of a form of UBS AG Subordinated Guarantee Agreement as an exhibit to the registration statement of which this prospectus is a part.

Guaranteed Obligations

In each UBS AG Subordinated Guarantee Agreement, UBS AG will, subject to the capital limitations, and as further provided herein, unconditionally guarantee, on a subordinated basis, the payment by the related UBS Preferred Funding Company of the following, without duplication:

•  any dividends on the related company preferred securities that are due and payable on any mandatory dividend payment date in an amount equal to the mandatory dividend payment;

•  any discretionary dividends on the related company preferred securities that become definitive because UBS AG does not deliver a no dividend instruction;

•  the redemption price payable with respect to any related company preferred securities called for redemption by the relevant UBS Preferred Funding Company;

•  the liquidating distribution on each related company preferred security payable upon liquidation of the relevant UBS Preferred Funding Company; and

•  any additional amounts payable by the relevant UBS Preferred Funding Company as described under “Description of Company Preferred Securities— Additional Amounts.”

Subject to the subordination provisions described below, UBS AG will be obligated to make such payments as and when due, regardless of any defense, right of set-off or counterclaim that the relevant UBS Preferred Funding Company may have or assert, other than the defense of payment, and whether or not the relevant UBS Preferred Funding Company has legally available funds for the guaranteed payments. UBS AG’s obligations under the UBS AG Subordinated Guarantee Agreements are several and independent of the obligations of each relevant UBS Preferred Funding Company with respect to its company preferred securities.

See “Description of Company Preferred Securities— Dividends” for a description of circumstances when dividend on company preferred securities are mandatory, “Description of Company Preferred Securities— Redemption” for a description of the company preferred securities’ redemption provisions, and “Description of Company Preferred Securities— Ranking and Liquidation Preference” for a description of the liquidation claim to which the holders are entitled in a liquidation of any UBS Preferred Funding Company.

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Description of UBS AG Subordinated Guarantees

Subordination

Each UBS AG subordinated guarantee will be a general and unsecured obligation of UBS AG and, in liquidation of UBS AG, will rank, both as to payment and in liquidation:

•  subordinate and junior to all deposits and other liabilities (including those in respect of bonds, notes and debentures of UBS AG) that do not expressly rank equally with the obligations of UBS AG under the relevant UBS AG Subordinated Guarantee Agreement, and

•  senior to the ordinary shares of UBS AG and any other securities or shares of UBS AG expressed to rank junior to the most senior preference shares of UBS AG (if any) from time to time outstanding.

The foregoing liabilities that rank senior to the UBS AG subordinated guarantees are collectively called “UBS AG senior liabilities.”

Payments under the UBS AG subordinated guarantees (other than payments upon a winding-up or dissolution, by bankruptcy or otherwise, in Switzerland of UBS AG as provided below) will be conditional upon UBS AG not being in default in the payment of UBS AG senior liabilities and being solvent at the time of payment. A report as to the insolvency of UBS AG by two persons, each being a managing director, director or other authorized officer or agent of UBS AG or employees of the independent accountants of UBS AG will, in the absence of manifest error be treated and accepted by UBS AG, the holders of company preferred securities and all other interested parties as correct and sufficient evidence thereof.

If UBS AG is liquidated, whether voluntarily or involuntarily, (i) each UBS Preferred Funding Company will be liquidated and (ii) under the UBS AG Subordinated Guarantee Agreements, the holders of related company preferred securities (whether through a UBS Preferred Funding Trust or as direct holders who have withdrawn their related company preferred securities from a UBS Preferred Funding Trust) will have a claim entitling them to substantially the same liquidating distributions in the liquidation of UBS AG that they would have been entitled to if they had purchased preferred shares of UBS AG having an aggregate liquidation preference equal to the aggregate liquidation preference of their related company preferred securities and bearing dividends at the rate of dividends applicable to their related company preferred securities. Each UBS AG Subordinated Guarantee Agreement and each related UBS Preferred Funding Company’s LLC Agreement, taken together, will provide that the holders of company preferred securities of the relevant UBS Preferred Funding Company will not receive liquidating distributions in a liquidation of such UBS Preferred Funding Company and payments under the related UBS AG subordinated guarantee that, taken together, exceed the liquidating distributions to which they would have been entitled had they instead owned noncumulative perpetual preferred shares of UBS AG with equivalent terms as described above.

The subordination provisions set out above will be irrevocable. UBS AG will not be permitted to create or permit to exist any charge or other security interest over its assets to secure its obligations in respect of the UBS AG subordinated guarantees.

The obligations of UBS AG in respect of the UBS AG subordinated guarantees will be, prior to the winding up or dissolution of UBS AG, conditional upon UBS AG being solvent immediately before and after payment by the Cayman Islands branch. If this condition is not satisfied, any amounts that might otherwise have been allocated in or towards payment in respect of a UBS AG subordinated guarantee will be used to absorb losses of UBS AG.

The Swiss Federal Banking Commission has the right to impose protective or development measures and finally to impose the liquidation of UBS AG in case of danger of insolvency pursuant to Article 25 et seq. of the Swiss Banking Law.

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Description of UBS AG Subordinated Guarantees

As used in this prospectus and the applicable prospectus supplement:

“assets” means the consolidated gross assets of UBS AG.

“liabilities” means the consolidated gross liabilities of UBS AG, all as shown by the latest published audited consolidated balance sheet of UBS AG as adjusted for contingencies and for subsequent events, all valued in such manner as UBS AG or any liquidator (as the case may be) may determine and calculated in accordance with International Financial Reporting Standards.

“solvent” means (i) UBS AG is able to pay its debts as they fall due and (ii) UBS AG’s assets exceed its liabilities (other than its liabilities to persons who are not senior creditors).

Subject to applicable law, no beneficiary of the UBS AG subordinated guarantees will be able to exercise, claim or plead any right of set-off, compensation or retention in respect of any amount owed to it by UBS AG arising under or in connection with the UBS AG subordinated guarantees and each beneficiary of the UBS AG subordinated guarantees will, by virtue of being a beneficiary of the UBS AG subordinated guarantees, be deemed to have waived all such rights to set-off, compensation or retention.

Additional Amounts

UBS AG will make all payments under the UBS AG subordinated guarantees without withholding or deducting for, or on account of, any present or future tax, duties, assessments or governmental charges imposed or levied by Switzerland or the jurisdiction of residence of the issuer of any subordinated notes held by any UBS Preferred Funding Company or from which any payment on such notes is made or any authority of any of those jurisdictions that has the power to tax, unless UBS AG is required by law to withhold or deduct the present or future tax, duties, assessments or governmental charges. If UBS AG is required to withhold or deduct any portion of a payment, UBS AG will pay additional amounts in order to cause the net amounts received by the holders of the relevant trust preferred securities and company preferred securities to be the same as the holders would have received in the absence of the withholding or deduction, subject to the same limitations or additional amounts payable by each UBS Preferred Funding Company as described above under “Description of Company Preferred Securities—Additional Amounts.”

If payment of the amounts described above cannot be made by reason of any limitation referred to above, those amounts will be payable in proportion to the amounts that would have been payable but for that limitation.

Other Provisions

The relevant guarantee trustee, on behalf of the holders of the related company preferred securities, may enforce each UBS AG subordinated guarantee directly against UBS AG if UBS AG defaults under such UBS AG subordinated guarantee. Each UBS AG Subordinated Guarantee Agreement will provide that, to the fullest extent permitted by law, without the need for any other action of any person, including the relevant guarantee trustee or any other holder of related trust preferred securities or related company preferred securities, each holder of related trust preferred securities or related company preferred securities will be entitled to enforce the rights of the holders of such company preferred securities under the related UBS AG Subordinated Guarantee Agreement represented by the trust preferred securities or company preferred securities held by such holder.

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Description of UBS AG Subordinated Guarantees

Certain Covenants of UBS AG and the UBS Preferred Funding Companies

Issuance and Guarantee of Preference Shares

UBS AG will not issue any preferred or preference shares with liquidation rights effectively ranking senior to its obligations under the UBS AG subordinated guarantees or give any guarantee in respect of any of its preferred shares or preferred shares issued by any of its subsidiaries if the guarantee would rank senior to the UBS AG subordinated guarantees unless the UBS AG subordinated guarantees are amended to give the holders of related company preferred securities and the related trust preferred securities the same rights and entitlements as are contained in or attached to the other guarantees so that the UBS AG subordinated guarantees rank equally with those guarantees and, from a financial point of view, effectively, with those preferred shares. Except to the extent described above, the UBS AG subordinated guarantees do not limit the incurrence or issuance of other secured or unsecured debt or other obligations of UBS.

Payment of Dividends

UBS AG will agree in the UBS AG subordinated guarantees that if any amount required to be paid under the UBS AG subordinated guarantees in respect of any dividends on related trust preferred securities or related company preferred securities payable in respect of the most recent dividend period has not been paid, UBS AG will pay that amount before paying any dividend or other payment on any UBS AG junior obligations, except dividends in the form of the ordinary shares.

No Assignment

UBS AG will not be permitted to assign its obligations under the UBS AG subordinated guarantees, except in the case of merger, consolidation or sale of substantially all of its assets where UBS AG is not the surviving entity.

Termination

Each UBS AG subordinated guarantee will terminate on the earlier of:

•  the payment of the redemption price for all related company preferred securities or purchase and cancellation of all related company preferred securities, and

•  full payment of the liquidating distribution on all related company preferred securities.

However, each UBS AG subordinated guarantee will continue to be effective or will be reinstated, as the case may be, if the holder is required to return any payment made under the related company preferred securities or the related UBS AG subordinated guarantee.

Amendments

Any changes to the provisions of a UBS AG subordinated guarantee that establish the amount and timing of the payments under that UBS AG subordinated guarantee must be approved by each holder of related company preferred securities. Any other provision of a UBS AG subordinated guarantee may be modified only with the prior approval of the holders of not less than two-thirds (based on the aggregate liquidation preference) of the related company preferred securities.

Notwithstanding the foregoing, without the consent of any holder of related company preferred securities, UBS AG may amend or supplement each UBS AG Subordinated Guarantee Agreement:

•  to conform any change in the Investment Company Act, the Trust Indenture Act or the rules or regulations of either such Act,

•  to add to the covenants, restrictions or obligations of UBS AG,

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Description of UBS AG Subordinated Guarantees

•  to modify, eliminate and add to any provision to such extent as may be necessary or desirable under such UBS AG Subordinated Guarantee Agreement, so long as any such action shall not materially adversely affect the rights, preferences or privileges of the holders of related company preferred securities, or

•  to cure any ambiguity or to correct or supplement any provision in such UBS AG Subordinated Guarantee that may be defective or inconsistent with any other provision therein.

Information Concerning the Guarantee Trustee

Wilmington Trust Company will be the guarantee trustee. The guarantee trustee will be required to perform only those duties that are specifically set forth in the UBS AG subordinated guarantees, except when a default has occurred and is continuing with respect to any UBS AG subordinated guarantee. After a default, the guarantee trustee will be required to exercise the same degree of care a prudent person would exercise under the circumstances in the conduct of his or her own affairs. Subject to these requirements, the guarantee trustee is under no obligation to exercise any of the powers vested in it by any UBS AG subordinated guarantee at the request of any holder of related company preferred securities or any holder of related trust preferred securities, as the case may be, unless the holder offers the guarantee trustee reasonable indemnity against the costs, expenses and liabilities that might be incurred by exercising those powers.

Governing Law

The UBS AG subordinated guarantees will be governed by and construed in accordance with the laws of the State of New York.

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Description of Subordinated Notes of UBS AG

The following summary of the material terms and provisions of the subordinated notes is not complete and is subject to, and qualified in its entirety by reference to, the terms and provisions of the subordinated notes. We have filed a copy of the form of subordinated note as an exhibit to the registration statement of which this prospectus is a part.

General

Each UBS Preferred Funding Company will apply the proceeds of its company preferred securities and company common securities to purchase from the Cayman Islands branch of UBS AG newly issued subordinated notes of the Cayman Islands branch. The subordinated notes are undated obligations of UBS AG, acting through the Cayman Islands branch. Interest on the subordinated notes will be payable from the date of initial issuance on the dates specified in the applicable prospectus supplement—which dates will correspond to the dividend payment dates of the related company preferred securities—(each, an “interest payment date” and the period from and including an interest payment date, or the date of initial issuance, as applicable, to but not including the next interest payment date, an “interest period”) for each interest period, at a fixed or floating rate specified in the applicable prospectus supplement.

Interest due on an interest payment date will be deferrable at the option of UBS AG’s Cayman Islands branch to the extent that dividends on the related company preferred securities due on the corresponding dividend payment date would constitute nondefinitive dividends. Interest deferred in this manner will not itself bear interest.

Redemption

Unless otherwise specified in the applicable prospectus supplement, the subordinated notes will be redeemable with the consent of the Swiss Federal Banking Commission and at the option of the Cayman Islands branch of UBS AG:

•  on or after the date specified in the applicable prospectus supplement, in whole or in part, at a redemption price equal to 100% of their principal amount plus interest accrued but unpaid to the date fixed for redemption.

•  prior to the date specified in the applicable prospectus supplement, in whole but not in part, if a Tax Event, an Investment Company Act Event or a Capital Event occurs, at a redemption price equal to 100% of their principal amount plus interest accrued but unpaid to the date fixed for redemption.

Additional Amounts

If the Cayman Islands branch of UBS AG is required to withhold any taxes, duties or other governmental charges with respect to any payment in respect of any subordinated notes, the Cayman Islands branch will pay such additional amounts as shall be required so that the amount received by each UBS Preferred Funding Company under the related subordinated notes shall not be reduced as a result of any such additional taxes, duties or other governmental charges.

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Description of Subordinated Notes of UBS AG

Subordination

The subordinated notes are a general and unsecured obligation of UBS AG and, in liquidation of UBS AG, will rank, both as to payment and in liquidation:

•  subordinate and junior to UBS AG senior liabilities, as defined under “Description of UBS AG Subordinated Guarantees—Subordination,” and

•  senior to the ordinary shares of UBS AG and any other securities or shares of UBS AG expressed to rank junior to the most senior preference shares of UBS AG (if any) from time to time outstanding.

Payments under any subordinated notes (other than payments upon a winding-up or dissolution, by bankruptcy or otherwise, in Switzerland of UBS AG) are conditional upon UBS AG not being in default in the payment of UBS AG senior liabilities, and being solvent, as defined under “Description of UBS AG Subordinated Guarantees—Subordination,” at the time of payment. A report as to the insolvency of UBS AG by two persons, each being a managing director, director or other authorized officer or agent of UBS AG or employees of the independent accountants of UBS AG will, in the absence of manifest error be treated and accepted by UBS AG, the holders of the company preferred securities and all other interested parties as correct and sufficient evidence thereof.

Enforcement of Subordinated Notes

Any consent, notice or other action (including any enforcement action) given or taken by or on behalf of a UBS Preferred Funding Company with respect to related subordinated notes may be given or taken at the discretion of a majority of the entire board of directors of such UBS Preferred Funding Company.

Transfer of Subordinated Notes

The subordinated notes held by a UBS Preferred Funding Company will be represented by a single definitive note registered in the name of such UBS Preferred Funding Company. Each UBS Preferred Funding Company’s LLC Agreement provides that any UBS Preferred Funding Company may sell its subordinated notes only upon the affirmative vote of both a majority of the board of directors of such UBS Preferred Funding Company and the holders of two-thirds (based on the aggregate liquidation preference) of its company preferred securities and other company parity preferred securities (if any), voting together as a single class.

Although each UBS Preferred Funding Company will be permitted to sell its subordinated notes subject to the requirements of the Securities Act of 1933 and other applicable laws and the foregoing requirements, neither UBS AG nor any UBS Preferred Funding Company anticipates that any UBS Preferred Funding Company will sell its subordinated notes and there is no expectation that a market will develop or exist for any subordinated notes. Unless otherwise specified in the applicable prospectus supplement, any subordinated notes, by their terms, will provide that they may be sold in whole and not in part and may not be divided into denominations of less than USD25 or USD1000, as the case may be.

Events of Default

No subordinated notes will provide for acceleration if the Cayman Islands branch of UBS AG fails to make a payment when due. If the Cayman Islands branch fails to make a payment when due of an installment of interest on any subordinated notes, the related UBS Preferred Funding Company will be entitled to seek to enforce payment only of the defaulted installment but not in respect of any failure to pay interest due under the related subordinated notes that was deferred because the dividends on its

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Description of Subordinated Notes of UBS AG

company preferred securities on the corresponding dividend payment date would have constituted nondefinitive dividends. A “default” under any subordinated notes will occur if the Cayman Islands branch fails to make a payment when due of an installment of principal or interest.

Modification and Amendment of Subordinated Notes

Any subordinated notes will be able to be modified or amended only by the written agreement of the Cayman Islands branch of UBS AG and the related UBS Preferred Funding Company. However, each UBS Preferred Funding Company’s LLC Agreement will provide that no UBS Preferred Funding Company may agree to any such modification or amendment for so long as any of its company preferred securities or other company parity preferred securities, if any, are outstanding unless holders of two-thirds (based on the aggregate liquidation preference) of its company preferred securities and other company parity preferred securities, if any, voting as a class, consent to such modification or amendment (except that such consent of the holders of its company preferred securities and any other company parity preferred securities shall not be required if (a) the proposed amendment or modification would not materially and adversely affect the rights, preferences, powers or privileges of such UBS Preferred Funding Company and (b) such UBS Preferred Funding Company has received a letter from each of Moody’s Investors Service, Inc. and Standard & Poor’s Ratings Services to the effect that such amendment will not result in a downgrading of its respective rating then assigned to its company preferred securities).

Governing Law

The subordinated notes will be governed by the laws of the State of New York.

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Description of Subordinated Notes of UBS AG

U.S. Tax Considerations

In the opinion of Sullivan & Cromwell LLP, the following, unless otherwise stated in the applicable prospectus supplement relevant to the trust preferred securities being offered thereby, accurately describes the material United States federal income tax (and, where specifically noted, United States federal estate tax) consequences of the purchase of the trust preferred securities and the ownership and disposition of the trust preferred securities and the company preferred securities.

YOU SHOULD CONSULT WITH YOUR OWN TAX ADVISORS AS TO THE UNITED STATES FEDERAL INCOME TAX CONSEQUENCES OF THE PURCHASE, OWNERSHIP AND DISPOSITION OF THE TRUST PREFERRED SECURITIES OR THE COMPANY PREFERRED SECURITIES, AS WELL AS THE EFFECT OF ANY STATE, LOCAL OR FOREIGN TAX LAWS IN LIGHT OF YOUR PARTICULAR CIRCUMSTANCES.

This discussion addresses only the tax consequences to a person that acquires the trust preferred securities on their original issue at their original offering price and that holds the trust preferred securities, and any company preferred securities received in exchange for the trust preferred securities, as capital assets. It does not address all tax consequences that may be applicable to a beneficial owner of the trust preferred securities or company preferred securities nor does it address the tax consequences to:

• persons that may be subject to special treatment under United States federal income tax law, such as tax-exempt entities, certain insurance companies, broker-dealers, traders in securities that elect to mark to market, persons liable for alternative minimum tax or persons that actually or constructively own 10% or more of the voting stock of UBS AG,

• persons that will hold the trust preferred securities or the company preferred securities as part of a larger transaction, such as a “straddle” or a “hedging” or “conversion” or other integrated transaction, or

• United States Holders (as defined below) whose functional currency is not the United States dollar.

If a partnership holds the trust preferred securities, the United States federal income tax treatment of a partner will generally depend on the status of the partner and the tax treatment of the partnership. If you are a partner in a partnership holding the trust preferred securities, you should consult your tax advisor with regard to the United States federal income tax treatment of the investment in the trust preferred securities.

This discussion assumes that the applicable UBS Preferred Funding Company will hold no assets other than the UBS AG subordinated notes. If the applicable UBS Preferred Funding Company will hold assets other than the UBS AG subordinated notes, you should consult your tax advisor with regard to the United States federal income tax treatment of your investment in the trust preferred securities.

This discussion is based upon the Internal Revenue Code of 1986, as amended, Treasury regulations, Internal Revenue Service rulings and pronouncements and judicial decisions as of the date hereof, all of which are subject to change, possibly with retroactive effect.

Classification of the UBS Preferred Funding Trusts and the UBS Preferred Funding Companies

Under current law, and assuming compliance with the terms of each Amended and Restated Trust Agreement in the form attached as an exhibit hereto, each UBS Preferred Funding Trust will not be treated as an association taxable as a corporation for United States federal income tax purposes. In addition, we intend to treat each UBS Preferred Funding Trust as a grantor trust for United States federal income tax purposes, and the discussion below assumes that the applicable UBS Preferred

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U.S. Tax Considerations

Funding Trust will in fact be treated as a grantor trust for United States federal income tax purposes. As a result, each beneficial owner of the trust preferred securities will be considered the beneficial owner of a pro rata portion of the related company preferred securities held by the applicable UBS Preferred Funding Trust. If the applicable UBS Preferred Funding Trust were to be treated as a partnership for United States federal income tax purposes, the treatment of a beneficial owner of the trust preferred securities s would not be materially different from the treatment described below, except that U.S. tax information will be provided to such beneficial owners and to the Internal Revenue Service on Schedule K-1, rather than in the manner described below under “—Information Reporting and Backup Withholding.”

Under current law, each UBS Preferred Funding Company will be treated as a partnership for United States federal income tax purposes. A partnership is not a taxable entity and incurs no United States federal income tax liability. Instead, each partner is required to take into account its allocable share of items of income, gain, loss and deduction of the partnership in computing its United States federal income tax liability, regardless of whether distributions are made to the partner. These items generally will be treated as if realized by the partner directly from the same source realized by the applicable UBS Preferred Funding Company.

United States Holders

You are a “United States Holder” if you are a beneficial owner of the trust preferred securities or company preferred securities and you are:

• an individual citizen or resident of the United States,

• a corporation organized in or under the laws of the United States or any state thereof or the District of Columbia,

• an estate, and your income is subject to United States federal income tax regardless of source, or

• a trust, if

  • a United States court is able to exercise primary supervision over your administration, and

  • one or more United States persons are authorized to control all substantial decisions of the trust.

Income from the Trust Preferred Securities

Under the applicable Amended and Restated LLC Agreement in the form attached as an exhibit hereto, upon the payment, or deemed payment, of dividends on the company preferred securities, a like amount of the applicable UBS Preferred Funding Company’s ordinary income generally will be allocated to the holders of company preferred securities. Regardless of when dividends on the related trust preferred securities are actually paid, income allocated to the holders of company preferred securities will be includable as ordinary income by a United States Holder for its taxable year that includes 31 December of the calendar year in which the income is allocated, except that if the United States Holder disposes of its entire holding of the trust preferred securities and company preferred securities (if any), the amount allocated for the calendar year of that disposition will be includable for the United States Holder’s taxable year that includes the date of that disposition.

Dividends paid by a “qualified foreign corporation” to a non-corporate United States Holder in taxable years beginning before January 1, 2009 are generally subject to a preferential rate of tax for United States federal tax purposes if the beneficial recipient of the dividend satisfies certain minimum holding period requirements and the dividend is paid out of the current or accumulated earnings and profits of the foreign corporation (as determined for United States federal income tax purposes). The subordinated notes held by the applicable UBS Preferred Funding Company should be treated as equity

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U.S. Tax Considerations

of UBS AG. Furthermore, UBS AG should currently be treated as a “qualified foreign corporation” for United States federal income tax purposes. Accordingly, amounts included in income by a non-corporate United States Holder with respect to its trust preferred securities in taxable years beginning before January 1, 2009 should generally be subject to a preferential rate of tax for United States federal income tax purposes, provided that (a) the United States Holder satisfies certain minimum holding period requirements and (b) the payments on the subordinated notes are paid out of the current or accumulated earnings and profits of UBS AG. Special rules apply in determining the foreign tax credit limitation with respect to dividends that are subject to tax at a preferential rate.

Assuming compliance with the terms of the applicable Amended and Restated Trust Agreement in the form attached as an exhibit hereto, each UBS Preferred Funding Trust will distribute, until the date and otherwise in the manner specified in the applicable prospectus supplement, an amount of cash equal to all of the income that is allocated to it as a holder of company preferred securities. As a consequence, a United States Holder generally will not recognize income in respect of trust preferred securities without receiving the corresponding cash distribution, unless the United States Holder sells or otherwise disposes of those trust preferred securities between the payment date of dividends on the related company preferred securities and the corresponding record date for dividends on the trust preferred securities. In the case of a sale between those dates, a United States Holder generally will recognize ordinary income in an amount equal to the dividends on the company preferred securities, which would increase the United States Holder’s basis in the trust preferred securities and reduce the gain, or increase the loss, recognized on the sale or other disposition.

A United States Holder’s allocated share of the applicable UBS Preferred Funding Company’s income from the subordinated notes will be foreign source income for purposes of determining the limitation on any allowable foreign tax credit. The overall limitation on foreign taxes eligible for credit is calculated separately with respect to specific classes of income. For this purpose, a United States Holder’s allocated share of each UBS Preferred Funding Company’s income from the subordinated notes for taxable years beginning before January 1, 2007 generally will constitute “passive income” or, in the case of certain United States Holders, “financial services income” and for taxable years beginning after December 31, 2006 generally will constitute “passive income” or, in the case of certain United States Holders, “general income.” If, with respect to any distribution to a United States Holder, additional amounts are paid by the applicable UBS Preferred Funding Company as a result of withholding taxes imposed on the distribution, those additional amounts will be taxable to the United States Holder as foreign source income. However, withholding taxes in the amount of those additional amounts will generally be treated as foreign income taxes eligible for credit against that United States Holder’s United States federal income tax liability, subject to generally applicable limitations and conditions or, at the election of that United States Holder, for deduction in computing the United States Holder’s taxable income.

No portion of the income derived by a United States Holder from the trust preferred securities will be eligible for the dividends-received deduction generally available to United States corporations in respect of dividends received from other United States corporations.

UBS AG believes that it is not a “passive foreign investment company” (sometimes known as a “PFIC”) for United States federal income tax purposes, but this conclusion is a factual determination made annually and thus may be subject to change. A United States Holder might be subject to special rules with respect to certain amounts earned by the applicable UBS Preferred Funding Company with respect to the initial subordinated notes if UBS AG were treated as a PFIC for United States federal income tax purposes.

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U.S. Tax Considerations

Receipt of the Company Preferred Securities upon Liquidation of each UBS Preferred Funding Trust

Under certain circumstances, the company preferred securities may be distributed to trust preferred securityholders in exchange for their trust preferred securities and in liquidation of the applicable UBS Preferred Funding Trust. Unless the liquidation of the applicable UBS Preferred Funding Trust occurs as a result of that UBS Preferred Funding Trust being subject to United States federal income taxes, such a distribution to a United States Holder would be treated, for United States federal income tax purposes, as a non-taxable event. Each United States Holder would receive an aggregate tax basis in the company preferred securities equal to the United States Holder’s aggregate tax basis in its trust preferred securities and the United States Holder’s holding period in the company preferred securities received would include the period during which the trust preferred securities were held by the United States Holder. If, however, the liquidation of the applicable UBS Preferred Funding Trust were to occur because that UBS Preferred Funding Trust is subject to United States federal income taxes, the distribution of the company preferred securities to United States Holders by the applicable UBS Preferred Funding Trust would likely be a taxable event to each United States Holder, and a United States Holder would recognize gain or loss as if the United States Holder had exchanged its trust preferred securities for the company preferred securities it received. The gain or loss would be equal to the difference between the United States Holder’s aggregate tax basis in its trust preferred securities surrendered in the exchange and the aggregate fair market value of the company preferred securities received in the exchange.

If the company preferred securities are distributed to the holders of trust preferred securities in liquidation of the applicable UBS Preferred Funding Trust, under current law, U.S. tax information will be provided to beneficial owners of the company preferred securities and to the Internal Revenue Service on Schedule K-1, rather than in the manner described below under “—Information Reporting and Backup Withholding.”

Disposition of the Trust Preferred Securities or the Company Preferred Securities

A United States Holder will recognize gain or loss on a sale, exchange or other taxable disposition of the trust preferred securities or the company preferred securities in an amount equal to the difference between the United States Holder’s adjusted tax basis and the amount realized on the disposition. A United States Holder’s adjusted tax basis in the trust preferred securities generally will equal the amount paid for the trust preferred securities, increased by the amount of income allocated to the United States Holder and reduced by the amount of any cash, and the fair market value of any other property, distributed to the United States Holder. Any gain or loss so recognized generally will be capital gain or loss, will be long-term capital gain or loss if the United States Holder’s holding period is more than one year and will be U.S. source income or loss for purposes of determining the limitation on any allowable foreign tax credit. Capital gain of a non-corporate United States Holder is generally taxed at preferential rates where the property is held for more than one year.

The trust preferred securities may trade at a price that does not fully reflect the value of income that may have been allocated to a United States Holder with respect to the United States Holder’s trust preferred securities. A United States Holder that disposes of the trust preferred securities between the payment date of dividends on the company preferred securities and the corresponding record date for dividends on the trust preferred securities generally will be required to include as ordinary income an amount equal to dividends on the company preferred securities and to add the amount of that income to its adjusted tax basis in the trust preferred securities. Accordingly, such a United States Holder will recognize a capital loss to the extent that the selling price is less than the United States Holder’s adjusted tax basis. Subject to certain limited exceptions, capital losses cannot be applied to offset ordinary income for United States federal income tax purposes.

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U.S. Tax Considerations

Non-United States Holders

You are a “Non-United States Holder” if you are a beneficial owner of the trust preferred securities or the company preferred securities and you are for United States federal income tax purposes:

•  a nonresident alien individual,

•  a foreign corporation,

•  a foreign partnership, or

•  an estate or trust in either case that is not subject to United States federal income tax on a net income basis on income or gain from the trust preferred securities or company preferred securities.

Each UBS Preferred Funding Company intends to operate, and the discussion below assumes that it will in fact operate, so that it will not be engaged in a trade or business within the United States for United States federal income tax purposes. Moreover, Each UBS Preferred Funding Company intends to invest, and the discussion below assumes that it will in fact invest, in securities the income from which will be either generally exempt from United States federal withholding tax or exempt from United States federal withholding tax to the extent allocable to a Non-United States Holder.

A Non-United States Holder will not be subject to United States federal income or withholding tax on any allocated share of the applicable UBS Preferred Funding Company’s income or gain, or any gain realized on the sale or exchange of the trust preferred securities or company preferred securities, unless, in the case of gains, the Non-United States Holder is an individual who was present in the United States for 183 days or more in the taxable year in which the gain is realized and certain other conditions are met. A Non-United States Holder will not be subject to backup withholding provided certain certification requirements are satisfied as described under “—Information Reporting and Backup Withholding.”

The treatment of the trust preferred securities and the company preferred securities for United States federal estate tax purposes is unclear. If you are an individual Non-United States Holder or an entity the property of which is potentially includible in the gross estate of an individual Non-United States Holder for United States federal estate tax purposes (for example, a trust funded by an individual Non-United States Holder and with respect to which such holder has retained certain interests or powers), you should consult your tax advisor about the possibility that the trust preferred securities or the company preferred securities will be includable in the gross estate of the appropriate individual holder for purposes of the United States federal estate tax.

Information Reporting and Backup Withholding

If you are a noncorporate United States Holder, under current law the amount of income paid or accrued on the trust preferred securities will generally be reported to you on Internal Revenue Service Form 1099. For calendar years beginning after January 1, 2007, United States Holders, as “trust interest holders” in a “widely-held fixed investment trust,” will also receive an annual statement containing a detailed description of the tax information necessary for the United States Holder to compute its tax liability with respect to the trust preferred securities. In addition, information reporting will generally apply to the payment of proceeds to a noncorporate United States Holder from the disposition of the trust preferred securities effected at a United States office of a broker or at the office of a broker that is a United States person or has certain connections with the United States. Additionally, backup withholding may apply to such amount of income or payment of proceeds if you are a noncorporate United States Holder that:

•  fails to provide an accurate taxpayer identification number,

•  is notified by the Internal Revenue Service that you have failed to report all interest and dividends required to be shown on your federal income tax returns, or

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U.S. Tax Considerations

•  in certain circumstances, fails to comply with applicable certification requirements.

If you are a Non-United States Holder, you are generally exempt from backup withholding and information reporting requirements with respect to:

•  payments made on the trust preferred securities outside the United States by a non-U.S. payor, and

•  other payments made on the trust preferred securities and the payment of the proceeds from the disposition of the trust preferred securities effected at a United States office of a broker, as long as the income associated with such payments is otherwise exempt from United States federal income tax, and:

•  the payor or broker does not have actual knowledge or reason to know that you are a United States person and you have furnished the payor or broker:

•  an Internal Revenue Service Form W-8BEN or an acceptable substitute form upon which you certify, under penalties of perjury, that you are a non-United States person, or

•  other documentation upon which it may rely to treat the payments as made to a non-United States person in accordance with U.S. Treasury regulations, or

•  you otherwise establish an exemption.

Payment of the proceeds from the disposition of the trust preferred securities effected at a foreign office of a broker generally will not be subject to information reporting or backup withholding. However, a disposition of the trust preferred securities effected at a foreign office of a broker will be subject to information reporting and backup withholding if:

•  the proceeds are transferred to an account maintained by you in the United States,

•  the payment of proceeds or the confirmation of the sale is mailed to you at a United States address, or

•  the sale has some other specified connection with the United States as provided in U.S. Treasury regulations,

unless the broker does not have actual knowledge or reason to know that you are a United States person and the documentation requirements described above are met or you otherwise establish an exemption.

In addition, a disposition of the trust preferred securities effected at a foreign office of a broker will be subject to information reporting if the broker is:

•  a United States person,

•  a controlled foreign corporation for United States tax purposes,

•  a foreign person 50% or more of whose gross income is effectively connected with the conduct of a United States trade or business for a specified three-year period, or

•  a foreign partnership, if at any time during its tax year:

•  one or more of its partners are “U.S. persons”, as defined in U.S. Treasury regulations, who in the aggregate hold more than 50% of the income or capital interest in the partnership, or

•  such foreign partnership is engaged in the conduct of a United States trade or business,

unless the broker does not have actual knowledge or reason to know that you are a United States person and the documentation requirements described above are met or you otherwise establish an exemption. Backup withholding will apply if the sale is subject to information reporting and the broker has actual knowledge that you are a United States person.

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U.S. Tax Considerations

You generally may obtain a refund of any amounts withheld under the backup withholding rules that exceed your income tax liability by filing a refund claim with the United States Internal Revenue Service.

Under current law, U.S. tax information will be provided to beneficial owners of the company preferred securities and to the Internal Revenue Service on Schedule K-1, rather than in the manner described above.

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U.S. Tax Considerations

Tax Considerations Under the Laws of Switzerland

General

Unless as otherwise stated in the applicable prospectus supplement, this section describes the material Swiss tax consequences (corporate and individual income tax, wealth tax, withholding tax, stamp tax on the issuance of securities, stamp tax on the turnover of securities) of the acquisition, ownership and disposition of trust preferred securities and company preferred securities. The tax information set forth below is based on the opinion of Homburger, Zurich, Switzerland, dated March 24, 2006 and has been approved by them for its accuracy.

The following summary does not purport to address all tax consequences of the acquisition, ownership and disposition of trust preferred securities and company preferred securities, and does not take into account the specific circumstances of any particular investor. This summary is based on the tax legislation of Switzerland as in effect on the date hereof, which are subject to change (or subject to changes in interpretation), possibly with retroactive effect.

Holders or prospective holders of trust preferred securities or company preferred securities are advised to consult their own tax advisers in light of their particular circumstances as to the Swiss tax legislation that could be relevant for them in connection with acquiring, owning and disposing of the trust preferred securities or company preferred securities and receiving dividend, redemption or liquidation payments on the trust preferred securities or company preferred securities and the consequences of such actions under the tax legislation of Switzerland.

Withholding Tax

Dividend, redemption and liquidation payments on the trust preferred securities or the company preferred securities will not be subject to Swiss withholding tax (even though UBS AG guarantees, on a subordinated basis, dividend, redemption and liquidation payment obligations under the company preferred securities), provided that at all times the respective UBS Preferred Funding Trust and the respective UBS Preferred Funding Company are resident and effectively managed outside Switzerland, the Cayman Islands branch of UBS AG has the status of a bank and is a permanent establishment situated and effectively managed outside Switzerland and the respective proceeds from the sale of the trust preferred securities, the company preferred securities and the subordinated notes are (on a non-consolidated basis) booked and used outside Switzerland.

Stamp Taxes

The issuance of the trust preferred securities and the company preferred securities will not be subject to Swiss federal stamp tax on the issuance of securities (even though UBS AG guarantees, on a subordinated basis, dividend, redemption and liquidation payment obligations under the company preferred securities), provided that at all times the respective UBS Preferred Funding Trust and the respective UBS Preferred Funding Company are resident and effectively managed outside Switzerland, the Cayman Islands branch of UBS AG has the status of a bank and is a permanent establishment situated and effectively managed outside Switzerland and the respective proceeds from the sale of the trust preferred securities, the company preferred securities and the subordinated notes are (on a non-consolidated basis) booked and used outside Switzerland.

Dealings in trust preferred securities or company preferred securities where a bank or another securities dealer in Switzerland (as defined in the Swiss Federal Stamp Tax Act) acts as an intermediary, or is a party, to the transaction, may be subject to Swiss federal stamp tax on the turnover in securities at an aggregated rate of up to 0.3 percent of the purchase price of the trust

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Tax Considerations Under the Laws of Switzerland

preferred securities or the company preferred securities. A branch of UBS AG situated, or a subsidiary of UBS AG resident, outside Switzerland, which, in each case, is not a member of a Swiss stock exchange, will not be a Swiss securities dealer under the Swiss Federal Stamp Tax Act.

Swiss Federal, Cantonal and Communal Income and Wealth Taxation

Dividend, redemption and liquidation payments on trust preferred securities or company preferred securities to a holder who is not resident in Switzerland, and who, during the respective taxation year, has not engaged in a trade or business through a permanent establishment in Switzerland, and who is not subject to corporate or individual income taxation in Switzerland for any other reason will not be subject to any Swiss federal, cantonal or communal income tax.

Private individuals resident in Switzerland and holding the trust preferred securities or the company preferred securities in their private fortune, are required to include the dividend, redemption and liquidation payments (but not the repayments of nominal capital) on the trust preferred securities or the company preferred securities in their personal income tax return and are subject to Swiss federal, cantonal and communal income tax on any net taxable income (including the dividend, redemption and liquidation payments (but not the repayments of nominal capital) on the trust preferred securities or the company preferred securities) for the relevant taxation period. For private individuals capital gains resulting from the sale of the trust preferred securities or the company preferred securities are not subject to Swiss federal, cantonal and communal income tax; this is also the case for accrued interest. Capital losses are not tax-deductible. Swiss resident private individuals who hold the trust preferred securities or the company preferred securities as part of their private fortune are required to report their trust preferred securities or company preferred securities as part of their taxable wealth and will be subject to cantonal and communal wealth tax, provided that their net taxable wealth (including the trust preferred securities or the company preferred securities) exceeds applicable allowances.

Swiss-resident corporate entities, Swiss-resident private individuals as well as corporate entities and private individuals resident abroad who hold the trust preferred securities or the company preferred securities as part of a trade or business in Switzerland, in the case of residents abroad carried on through a permanent establishment situated in Switzerland, are required to recognize the dividend, redemption and liquidation payments on the trust preferred securities or the company preferred securities and capital gains or losses on the sale of the trust preferred securities or the company preferred securities in their income statement for the respective taxation period and are subject to Swiss federal, cantonal and communal individual or corporate income tax, as the case may be, on any net taxable earnings (including the dividend, redemption and liquidation payments on the trust preferred securities or the company preferred securities and capital gains or losses realized on the sale of the trust preferred securities or the company preferred securities) for such taxation period. The same taxation treatment also applies to Swiss-resident private individuals who, for income tax purposes, are classified as “professional securities dealers” for reasons of, inter alia, frequent dealing, or leveraged investments, in securities.

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Tax Considerations Under the Laws of Switzerland

ERISA Considerations

If you are a fiduciary of a pension, profit-sharing or other employee benefit plan subject to the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), you should review the fiduciary standards of ERISA and the plan’s particular circumstances before deciding to invest in the trust preferred securities. You should consider whether the investment would satisfy the prudence and diversification requirements of ERISA and whether the investment would be consistent with the terms of the plan and the other agreements which apply to plan investments.

The following summary of certain ERISA considerations relevant to investing in the trust preferred securities is subject to anything set forth in the applicable prospectus supplement relating to a particular offering of trust preferred securities.

A fiduciary of a plan subject to ERISA, as well as a person investing on behalf of an individual retirement account or a pension or profit-sharing plan for one or more self-employed persons, should also consider whether an investment in the trust preferred securities could result in a prohibited transaction. ERISA and the Internal Revenue Code of 1986, as amended (the “Code”), prohibit plans and individual retirement accounts from engaging in certain transactions involving plan assets with persons who are parties in interest under ERISA or disqualified persons under the Code with respect to the plan or individual retirement account. A violation of these rules may result in a substantial excise tax under the Code and other liabilities under ERISA. Employee benefit plans that are governmental plans, foreign plans or church plans generally are not subject to the prohibited transaction rules or the fiduciary standards of ERISA.

The assets of each UBS Preferred Funding Trust would be treated as plan assets for purposes of the prohibited transaction rules under a U.S. Department of Labor regulation if plans and individual retirement accounts purchase trust preferred securities, unless an exception under the regulation applies. The regulation provides an exception if the trust preferred securities are considered to be publicly-offered securities. Unless otherwise specified in an applicable prospectus supplement, the underwriters expect that the trust preferred securities will be publicly-offered securities under the regulation because:

• the underwriters expect that the trust preferred securities will be purchased initially by at least 100 persons who are independent of us and each other,

• the trust preferred securities can be transferred freely,

• the trust preferred securities are being sold through this prospectus which is part of an effective registration statement filed with the SEC, and

• the trust preferred securities will be timely registered with the SEC under the Securities Exchange Act of 1934.

If we are a party in interest or a disqualified person with respect to a plan or individual retirement account that buys the trust preferred securities, either directly or because we own banking or other subsidiaries, the sale could be treated as a prohibited transaction unless an administrative exemption issued by the Department of Labor applies. The Department of Labor has issued class exemptions that may apply to exempt transactions resulting from the purchase or holding of the trust preferred securities. Among those class exemptions are Prohibited Transaction Exemption:

• 96-23, for transactions determined by in-house asset managers;

• 95-60, for transactions involving insurance company general accounts;

• 91-38, for transactions involving bank collective investment funds;

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ERISA Considerations

• 90-1, for transactions involving insurance company separate accounts; and

• 84-14, for transactions determined by independent qualified asset managers.

These rules are very complicated and the penalties that may be imposed upon persons involved in prohibited transactions can be substantial. This makes it very important that fiduciaries or other persons considering purchasing the trust preferred securities on behalf of a benefit plan investor consult with their lawyer regarding what could happen if the assets of the applicable UBS Preferred Funding Trust were deemed to be plan assets and if the investor can use one of the above class exemptions or another applicable exemption.

A purchaser or holder of trust preferred securities or any interest therein will be deemed to have represented by its purchase and holding thereof that it either (a) is not an employee benefit plan and is not purchasing such securities on behalf of or with plan assets of any employee benefit plan or (b) is eligible for the exemptive relief available under Prohibited Transaction Exemption 96-23, 95-60, 91-38, 90-1 or 84-14 or another applicable exemption with respect to such holding.

Before relying on any of these exemptions, a purchaser must conclude that the exemption provides the necessary relief for all potential prohibited transactions arising from the purchase of and from holding the trust preferred securities. Neither the underwriters, UBS AG nor any of their respective affiliates, agents or representatives have or can represent that these exemptions apply with respect to any purchase of trust preferred securities by any holder.

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Plan of Distribution

We may sell any trust preferred securities in a public offering to or through one or more underwriters, dealers and agents. The names of the underwriters, dealers or agents involved in any particular offering of trust preferred securities, the liquidation amount of the trust preferred securities to be purchased by such underwriters, dealers or agents, any applicable commissions or discounts and detailed description of any underwriting arrangement will be set forth in the applicable prospectus supplement.

Because the National Association of Securities Dealers, Inc. (“NASD”) views the trust preferred securities as a direct participation program, any offering will be conducted in accordance with Rule 2810 of the Rules of Conduct of the NASD. The underwriters will not confirm initial sales to accounts over which they exercise discretionary authority without the prior written approval of the customer. In accordance with the Rules of Conduct of the NASD, in no situation will underwriting compensation exceed 8% of the aggregate liquidation amount of the trust preferred securities.

UBS Securities LLC and UBS Financial Services Inc. are affiliates of UBS. Rule 2720 of the Conduct Rules of the NASD imposes certain requirements when an NASD member such as UBS Securities LLC or UBS Financial Services Inc. distributes an affiliated company’s securities. UBS Securities LLC and UBS Financial Services Inc. have advised UBS that the offerings of the trust preferred securities will comply with the applicable requirements of Rule 2720.

Validity of the Securities

Unless otherwise provided in the applicable prospectus supplement, certain matters of Delaware law relating to the validity of any trust preferred securities and related company preferred securities will be passed upon by Richards, Layton & Finger, P.A., special Delaware counsel to UBS AG, the UBS Preferred Funding Trusts and the UBS Preferred Funding Companies. Unless otherwise provided in the applicable prospectus supplement, the validity of the subordinated notes and the UBS AG Subordinated Guarantee Agreements will be passed upon for UBS AG, the UBS Preferred Funding Trusts and the UBS Preferred Funding Companies by Sullivan & Cromwell LLP. Sullivan & Cromwell LLP will rely upon the opinions of Richards, Layton & Finger P.A., as to matters of Delaware law, and the opinions of Homburger, Swiss counsel to UBS AG, as to matters of Swiss law. Certain matters relating to United States federal income tax considerations will be passed upon for UBS AG, the UBS Preferred Funding Trusts and the UBS Preferred Funding Companies by Sullivan & Cromwell LLP.

Experts

The consolidated balance sheet of UBS AG at December 31, 2005 and 2004 and the related consolidated statement of income, cash flows and changes in shareholder’s equity for each of the three years in the period ended December 31, 2005 incorporated by reference into this prospectus have been audited by Ernst & Young Ltd., independent auditors as set forth in their report thereon incorporated by reference into this prospectus, and are included in reliance upon such report given upon the authority of such firm as experts in accounting and auditing.

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