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The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the related prospectus are not an offer to sell these securities and are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Filed Pursuant to rule 424(b)(2)
Registration No. 333-172955

SUBJECT TO COMPLETION, DATED MARCH 21, 2011
PRELIMINARY PROSPECTUS SUPPLEMENT TO PROSPECTUS DATED MARCH 21, 2011

5,000,000 Shares

Common Stock

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          We are offering up to 5,000,000 shares of our common stock. We will receive all of the net proceeds from the sale of such common stock.

          Our common stock is traded on the NASDAQ Global Market under the symbol "PANL." The last reported sale price of our common stock on the NASDAQ Global Market on March 18, 2011 was $46.57 per share.

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          Investing in our common stock involves risks. See "Risk Factors" beginning on page S-6 to read about factors you should consider before buying our common stock.

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          The underwriters may purchase up to an additional 750,000 shares of our common stock within 30 days after the date of this prospectus supplement to cover over-allotments, if any.

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          Delivery of the shares of common stock will be made on or about                      , 2011.

          Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the prospectus to which it relates is truthful or complete. Any representation to the contrary is a criminal offense.

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Goldman, Sachs & Co.

UBS Investment Bank

Canaccord Genuity    Cowen and Company    Needham & Company, LLC    Oppenheimer & Co.

Avian Securities, LLC    Davenport & Company LLC    Fagenson & Co., Inc.

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The date of this prospectus supplement is March     , 2011

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Prospectus Supplement

          You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or any related free writing prospectus that we may provide to you. We have not authorized anyone to provide you with information that is different. We are offering to sell these securities and seeking offers to buy these securities only in jurisdictions where the offers and sales are permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any related free writing prospectus and the documents incorporated by reference herein and therein is accurate only as of their respective dates.

          The terms "UDC," the "Company," "we" and "us" in this prospectus supplement refer to Universal Display Corporation and its subsidiaries, unless the context otherwise requires.

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AVAILABLE INFORMATION

          We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission, or the SEC. You may read and copy any materials we file at the SEC's Public Reference Room at 100 F Street, N.E., Washington, DC 20549. You may obtain information on the operation of the Public Reference Room by calling the SEC at 1-888-SEC-0330. The SEC maintains a website at www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC. Our SEC filings are also available to the public from our website at www.universaldisplay.com. However, the information on our website does not constitute a part of this prospectus supplement, nor is it incorporated by reference herein.

          In this document, we "incorporate by reference" certain information we file with the SEC, which means that we can disclose important information to you by referring to that information. The information incorporated by reference is considered to be a part of this prospectus supplement. Any statement contained in a document incorporated by reference herein shall be deemed to be modified or superseded for all purposes to the extent that a statement contained in this prospectus supplement or in any other subsequently filed document that is also incorporated or deemed to be incorporated by reference, modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement. We incorporate by reference the documents listed below:

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Our Annual Report on Form 10-K for the year ended December 31, 2010;



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Our Current Reports on Form 8-K filed with the SEC on January 6, 2011, February 7, 2011, March 8, 2011, March 10, 2011 and March 21, 2011;



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Our Definitive Proxy Statement for our 2010 Annual Meeting of Shareholders, filed with the SEC on April 26, 2010; and



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The description of our common stock that is contained in our Registration Statement on Form 8-A filed with the SEC on August 6, 1996.

          All reports and other documents subsequently filed by us pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934 (other than Current Reports furnished under Item 2.02 or Item 7.01 (including any financial statements or other exhibits relating thereto furnished pursuant to Item 9.01) of Form 8-K unless we otherwise state therein) after the date of this prospectus supplement shall be deemed to be incorporated by reference in this prospectus supplement and to be part hereof from the date of filing of such reports and other documents.

          We hereby undertake to provide without charge to each person, including any beneficial owner, to whom a copy of this prospectus supplement is delivered, upon written or oral request of any such person, a copy of any and all of the information that has been or may be incorporated by reference in this prospectus supplement, including any exhibits that are specifically incorporated by reference in such documents. Requests for such copies should be directed as follows:

Universal Display Corporation
375 Phillips Boulevard
Ewing, New Jersey 08618
(609) 671-0980

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CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS

          This prospectus supplement and the documents incorporated by reference in this prospectus supplement contain some "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements concern possible or assumed future events, results and business outcomes. These statements often include words such as "believe," "expect," "anticipate," "intend," "plan," "estimate," "seek," "will," "may" or similar expressions. These statements are based on assumptions that we have made in light of our experience in the industry, as well as our perceptions of historical trends, current conditions, expected future developments and other factors we believe are appropriate under the circumstances.

          As you read and consider this prospectus supplement, you should not place undue reliance on any forward-looking statements. You should understand that these statements involve substantial risk and uncertainty and are not guarantees of future performance or results. They depend on many factors that are discussed further in the section of this prospectus entitled "Risk Factors," including:

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the outcomes of our ongoing and future research and development activities, and those of others, relating to organic light emitting diode, or OLED, technologies and materials;



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our ability to access future OLED technology developments of our academic and commercial research partners;



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the potential commercial applications of and future demand for our OLED technologies and materials, and of OLED products in general;



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our ability to form and continue strategic relationships with manufacturers of OLED products;



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successful commercialization of products incorporating our OLED technologies and materials by OLED manufacturers, and their continued willingness to utilize our OLED technologies and materials;



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the comparative advantages and disadvantages of our OLED technologies and materials versus competing technologies and materials currently on the market;



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the nature and potential advantages of any competing technologies that may be developed in the future;



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our ability to compete against third parties with resources greater than ours;



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our ability to maintain and improve our competitive position following the expiration of our fundamental OLED patents;



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the adequacy of protections afforded to us by the patents that we own or license and the cost to us of maintaining, enforcing and defending those patents;



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our ability to obtain, expand and maintain patent protection in the future, and to protect our non patented intellectual property;



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our exposure to and ability to withstand third-party claims and challenges to our patents and other intellectual property rights;



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the payments that we expect to receive under our existing contracts with OLED manufacturers and the terms of contracts that we expect to enter into with OLED manufacturers in the future;



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our future capital requirements and our ability to obtain additional financing if and when needed;

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our future OLED technology licensing and OLED material revenues and results of operations; and



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general economic and market conditions.

          Changes or developments in any of these areas could affect our financial results or results of operations, and could cause actual results to differ materially from those contemplated by any forward-looking statements.

          All forward looking statements speak only as of the date of this prospectus supplement or the documents incorporated by reference, as the case may be. We do not undertake any duty to update any of these forward-looking statements to reflect events or circumstances after the date of this prospectus supplement, or to reflect the occurrence of unanticipated events.

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PROSPECTUS SUMMARY

          This summary may not contain all of the information that may be important to you. You should read this prospectus supplement, the accompanying prospectus, the information incorporated by reference in each, and any related free writing prospectus before making an investment decision. You should pay special attention to the "Risk Factors" section beginning on page S-6 of this prospectus supplement, as well as any "Risk Factor" included in any document incorporated by reference herein, to determine whether an investment in our common stock is appropriate for you.

General

          We are a leader in the research, development and commercialization of organic light emitting diode, or OLED, technologies and materials. OLEDs are thin, lightweight and power-efficient solid-state devices that emit light, making them highly suitable for use in full-color displays and as lighting products. OLED displays are capturing a growing share of the flat panel display market. We believe that this is because OLEDs offer potential advantages over competing display technologies with respect to power efficiency, contrast ratio, viewing angle, video response time and manufacturing cost. We also believe that OLED lighting products have the potential to replace many existing light sources in the future because of their high power efficiency, excellent color rendering index, low heat generation and novel form factor. Our technology leadership and intellectual property position should enable us to share in the revenues from OLED displays and lighting products as they enter mainstream consumer and other markets.

          Our primary business strategy is to further develop and license our proprietary OLED technologies to manufacturers of products for display applications, such as cell phones, portable media devices, tablets, laptop computers and televisions, and specialty and general lighting products. In support of this objective, we also develop new OLED materials and sell materials to those product manufacturers. Through our internal research and development efforts and our relationships with world-class partners such as Princeton University, the University of Southern California, the University of Michigan, Motorola Solutions, Inc. and PPG Industries, Inc., we have established a significant portfolio of proprietary OLED technologies and materials. We currently own, exclusively license or have the sole right to sublicense more than 1,000 patents issued and pending worldwide.

          We sell our proprietary OLED materials to customers for evaluation and use in commercial OLED products. We also enter into agreements with manufacturers of OLED display and lighting products under which we grant them licenses to practice under our patents and to use our proprietary know-how. At the same time, we work with these and other companies who are evaluating our OLED technologies and materials for possible use in commercial OLED display and lighting products.

Corporate Information

          Our corporation was organized under the laws of the Commonwealth of Pennsylvania in April 1985. Our business was commenced in June 1994 by a company then known as Universal Display Corporation, which had been incorporated under the laws of the State of New Jersey. On June 22, 1995, a wholly-owned subsidiary of ours merged into this New Jersey corporation. The surviving corporation in this merger became a wholly-owned subsidiary of ours and changed its name to UDC, Inc. Simultaneously with the consummation of this merger, we changed our name to Universal Display Corporation. UDC, Inc. now functions as an operating subsidiary of ours and has overlapping officers and directors. We have also formed other wholly-owned subsidiaries, including Universal Display Corporation Hong Kong, Ltd. (2008), Universal Display Corporation Korea, Inc. (2010) and Universal Display Corporation Japan, K.K. (2011). Our principal executive offices are

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located at 375 Phillips Boulevard, Ewing, New Jersey 08618 and our telephone number is (609) 671-0980. Our Internet address is www.universaldisplay.com. The information on our Internet site is not part of this prospectus.

THE OFFERING

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excludes 3,362,233 shares of common stock reserved for issuance under our equity incentive plans, under which 1,900,719 shares of common stock are subject to outstanding awards as of March 17, 2011;



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excludes 317,296 shares of common stock underlying currently outstanding warrants; and



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assumes that the underwriters' option to purchase up to 750,000 additional shares to cover over-allotments is not exercised.

Risk Factors

          Investing in our common stock involves risks. See "Risk Factors" beginning on page S-6 to read about factors you should consider before buying our common stock.

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RISK FACTORS

          Before purchasing our common stock, you should carefully consider the following risk factor and those set forth in our most recent Annual Report on Form 10-K, which is incorporated by reference in this prospectus supplement. See "Available Information." You should also carefully consider all of the other information in this prospectus supplement or incorporated by reference herein. Any of the risks incorporated by reference could have a material adverse impact on our business, prospects, results of operations and financial condition and could therefore have a negative effect on the trading price of our common stock. Additionally risks not currently known to us or that we now deem immaterial may also harm us and negatively affect your investment.

Risk related to this offering

          Our management will have broad discretion with respect to the use of proceeds of this offering. We have not identified specific uses for the proceeds of this offering. You will be relying on the judgment of our management regarding the application of the proceeds of this offering. The results and effectiveness of the use of proceeds are uncertain.

USE OF PROCEEDS

          The net proceeds from the sale of the securities offered hereby will be used for general corporate purposes, including the acquisition, development and license of properties, assets, entities or technologies. As of the date of this prospectus supplement, we have not identified as probable any specific material proposed uses of these proceeds.

PRICE RANGE OF OUR COMMON STOCK

          Our common stock is listed for trading on the NASDAQ Global Market under the symbol "PANL". The following table sets forth the quarterly high and low closing prices of our common stock on the NASDAQ Global Market for the periods indicated:

          On March 18, 2011, the closing sale price of our common stock as reported on the NASDAQ Global Market was $46.57 per share. The foregoing table shows only historical comparisons. These comparisons may not provide meaningful information to you in determining whether to purchase shares of our common stock. You are urged to obtain current market quotations for our common stock and to review carefully the other information contained in this prospectus supplement, the accompanying prospectus, the documents incorporated by reference in each, and any related free writing prospectus. See "Available Information".

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UNDERWRITING

          The Company and the underwriters named below have entered into an underwriting agreement with respect to the shares being offered. Subject to certain conditions, each underwriter has severally agreed to purchase the number of shares indicated in the following table. Goldman, Sachs & Co. is the representative of the underwriters.

          The underwriters are committed to take and pay for all of the shares being offered, if any are taken, other than the shares covered by the option described below unless and until this option is exercised.

          If the underwriters sell more shares than the total number set forth in the table above, the underwriters have an option to buy up to an additional 750,000 shares from the Company. They may exercise that option for 30 days. If any shares are purchased pursuant to this option, the underwriters will severally purchase shares in approximately the same proportion as set forth in the table above.

          The following table shows the per share and total underwriting discounts and commissions to be paid to the underwriters by the Company. Such amounts are shown assuming both no exercise and full exercise of the underwriters' option to purchase 750,000 additional shares.

Paid by the Company

          Shares sold by the underwriters to the public will initially be offered at the initial public offering price set forth on the cover of this prospectus. Any shares sold by the underwriters to securities dealers may be sold at a discount of up to $             per share from the initial public offering price. If all the shares are not sold at the initial public offering price, the representatives may change the offering price and the other selling terms. The offering of the shares by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part.

          The Company and other parties have agreed with the underwriters, subject to certain exceptions, not to dispose of or hedge any of their common stock or securities convertible into or exchangeable for shares of common stock during the period from the date of this prospectus continuing through the date 90 days after the date of this prospectus, except with the prior written consent of the representatives. This agreement does not apply to any existing employee benefit plans.

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          In connection with this offering, the underwriters may purchase and sell shares of common stock in the open market. These transactions may include short sales, stabilizing transactions and purchases to cover positions created by short sales. Short sales involve the sale by the underwriters of a greater number of shares than they are required to purchase in the offering. "Covered" short sales are sales made in an amount not greater than the underwriters' option to purchase additional shares from the Company in this offering. The underwriters may close out any covered short position by either exercising their option to purchase additional shares or purchasing shares in the open market. In determining the source of shares to close out the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase additional shares pursuant to the option granted to them. "Naked" short sales are any sales in excess of such option. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the common stock in the open market after pricing that could adversely affect investors who purchase in the offering. Stabilizing transactions consist of various bids for or purchases of common stock made by the underwriters in the open market prior to the completion of the offering.

          The underwriters may also impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the representatives have repurchased shares sold by or for the account of such underwriter in stabilizing or short covering transactions.

          Purchases to cover a short position and stabilizing transactions, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the market price of the Company's stock, and together with the imposition of the penalty bid, may stabilize, maintain or otherwise affect the market price of the common stock. As a result, the price of the common stock may be higher than the price that otherwise might exist in the open market. If these activities are commenced, they may be discontinued at any time. These transactions may be effected on NYSE, NASDAQ NMS or relevant exchange, in the over-the-counter market or otherwise.

          The Company may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with those derivatives, the third parties may sell securities covered by this prospectus, including in short sale transactions. If so, the third party may use securities pledged by the Company or borrowed from the Company or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from the Company in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter or will be identified in a post-effective amendment.

European Economic Area

          In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a Relevant Member State), each underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the Relevant Implementation Date) it has not made and will not make an offer of shares to the public in that Relevant Member State prior to the publication of a prospectus in relation to the shares which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the

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Relevant Implementation Date, make an offer of shares to the public in that Relevant Member State at any time:

          (a)     to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities;

          (b)     to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than €43,000,000 and (3) an annual net turnover of more than €50,000,000, as shown in its last annual or consolidated accounts;

          (c)     to fewer than 100 natural or legal persons (other than qualified investors as defined in the Prospectus Directive) subject to obtaining the prior consent of the representatives for any such offer; or

          (d)     in any other circumstances which do not require the publication by the issuer of a prospectus pursuant to Article 3 of the Prospectus Directive.

          For the purposes of this provision, the expression an "offer of shares to the public" in relation to any shares in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the shares to be offered so as to enable an investor to decide to purchase or subscribe the shares, as the same may be varied in that Relevant Member State by any measure implementing the Prospectus Directive in that Relevant Member State and the expression Prospectus Directive means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

United Kingdom

Each underwriter has represented and agreed that:

          (a)     it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the FSMA) received by it in connection with the issue or sale of the shares in circumstances in which Section 21(1) of the FSMA does not apply to the Issuer; and

          (b)     it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the shares in, from or otherwise involving the United Kingdom.

Hong Kong

          The shares may not be offered or sold by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), or (ii) to "professional investors" within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a "prospectus" within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.

Singapore

          This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the

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offer or sale, or invitation for subscription or purchase, of the shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore, or the SFA, (ii) to a relevant person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

          Where the shares are subscribed or purchased under Section 275 by a relevant person which is: (a) a corporation (which is not an accredited investor) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (b) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary is an accredited investor, shares, debentures and units of shares and debentures of that corporation or the beneficiaries' rights and interest in that trust shall not be transferable for 6 months after that corporation or that trust has acquired the shares under Section 275 except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA; (2) where no consideration is given for the transfer; or (3) by operation of law.

Japan

          The securities have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (the Financial Instruments and Exchange Law) and each underwriter has agreed that it will not offer or sell any securities, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan.

          The Company estimates that its share of the total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $200,000.

          The Company has agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act of 1933.

          The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. Certain of the underwriters and their respective affiliates have, from time to time, performed, and may in the future perform, various financial advisory and investment banking services for the issuer, for which they received or will receive customary fees and expenses.

          In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments of the issuer. The underwriters and their respective affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

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NOTICE TO CANADIAN RESIDENTS

Resale Restrictions

          The distribution of the shares in Canada is being made only on a private placement basis exempt from the requirement that we prepare and file a prospectus with the securities regulatory authorities in each province where trades of shares are made. Any resale of the shares in Canada must be made under applicable securities laws which may vary depending on the relevant jurisdiction, and which may require resales to be made under available statutory exemptions or under a discretionary exemption granted by the applicable Canadian securities regulatory authority. Purchasers are advised to seek legal advice prior to any resale of the shares.

Representations of Purchasers

          By purchasing the common stock in Canada and accepting delivery of a purchase confirmation, a purchaser is representing to us and the dealer from whom the purchase confirmation is received that:

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the purchaser is entitled under applicable provincial securities laws to purchase the common stock without the benefit of a prospectus qualified under those securities laws as it is an "accredited investor" as defined under National Instrument 45-106 — Prospectus and Registration Exemptions,



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the purchaser is a "permitted client" as defined in National Instrument 31-103 — Registration Requirements and Exemptions,



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where required by law, the purchaser is purchasing as principal and not as agent,



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the purchaser has reviewed the text above under "Resale Restrictions", and



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the purchaser acknowledges and consents to the provision of specified information concerning the purchase of the common stock to the regulatory authority that by law is entitled to collect the information, including certain personal information. For purchasers in Ontario, questions about such indirect collection of personal information should be directed to Administrative Support Clerk, Suite 1903, Box 55, 20 Queen Street West, Toronto, Ontario M5H 3S8 or on (416) 593-3684.

Rights of Action — Ontario Purchasers Only

          Under Ontario securities legislation, certain purchasers who purchase a security offered by this prospectus during the period of distribution will have a statutory right of action for damages, or while still the owner of the common stock, for rescission against us in the event that this prospectus contains a misrepresentation without regard to whether the purchaser relied on the misrepresentation. The right of action for damages is exercisable not later than the earlier of 180 days from the date the purchaser first had knowledge of the facts giving rise to the cause of action and three years from the date on which payment is made for the common stock. The right of action for rescission is exercisable not later than 180 days from the date on which payment is made for the common stock. If a purchaser elects to exercise the right of action for rescission, the purchaser will have no right of action for damages against us. In no case will the amount recoverable in any action exceed the price at which the common stock was offered to the purchaser and if the purchaser is shown to have purchased the securities with knowledge of the misrepresentation, we will have no liability. In the case of an action for damages, we will not be liable for all or any portion of the damages that are proven to not represent the depreciation in value of the common stock as a result of the misrepresentation relied upon. These rights are in addition to, and without derogation from, any other rights or remedies available at law to an Ontario

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purchaser. The foregoing is a summary of the rights available to an Ontario purchaser. Ontario purchasers should refer to the complete text of the relevant statutory provisions.

Enforcement of Legal Rights

          All of our directors and officers as well as the experts named herein may be located outside of Canada and, as a result, it may not be possible for Canadian purchasers to effect service of process within Canada upon us or those persons. All or a substantial portion of our assets and the assets of those persons may be located outside of Canada and, as a result, it may not be possible to satisfy a judgment against us or those persons in Canada or to enforce a judgment obtained in Canadian courts against us or those persons outside of Canada.

Taxation and Eligibility for Investment

          Canadian purchasers of the common stock should consult their own legal and tax advisors with respect to the tax consequences of an investment in the common stock in their particular circumstances and about the eligibility of the common stock for investment by the purchaser under relevant Canadian legislation.

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LEGAL MATTERS

          The validity of the shares of common stock offered hereby will be passed upon for us by Morgan, Lewis & Bockius LLP, Philadelphia, Pennsylvania. Goodwin Procter LLP, Boston, Massachusetts is representing the underwriters in this offering.

EXPERTS

          The consolidated financial statements of Universal Display Corporation and subsidiaries as of December 31, 2010 and 2009, and for each of the years in the three-year period ended December 31, 2010, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2010, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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PROSPECTUS

Common Stock

        We may offer shares of our common stock. Our common stock is listed on the NASDAQ Global Market, where it trades under the symbol "PANL."

        We may offer our common stock at prices and on terms to be set forth in one or more supplements to this prospectus. Our common stock may be offered directly, through agents on our behalf or through underwriters or dealers.

        You should carefully read and consider the risk factors included in our periodic reports and other information that we file with the Securities and Exchange Commission before you invest in the securities described in this prospectus.

        The securities described in this prospectus have not been approved by the Securities and Exchange Commission or any state securities commission, nor have they determined if this prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is March 21, 2011

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CAUTIONARY STATEMENT
CONCERNING FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference in this prospectus contain some "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements concern possible or assumed future events, results and business outcomes. These statements often include words such as "believe," "expect," "anticipate," "intend," "plan," "estimate," "seek," "will," "may" or similar expressions. These statements are based on assumptions that we have made in light of our experience in the industry, as well as our perceptions of historical trends, current conditions, expected future developments and other factors we believe are appropriate under the circumstances.

        As you read and consider this prospectus, you should not place undue reliance on any forward-looking statements. You should understand that these statements involve substantial risk and uncertainty and are not guarantees of future performance or results. They depend on many factors that are discussed further in the section of this prospectus entitled "Risk Factors," including:

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the outcomes of our ongoing and future research and development activities, and those of others, relating to organic light emitting diode (OLED) technologies and materials;



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our ability to access future OLED technology developments of our academic and commercial research partners;



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the potential commercial applications of and future demand for our OLED technologies and materials, and of OLED products in general;



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our ability to form and continue strategic relationships with manufacturers of OLED products;



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successful commercialization of products incorporating our OLED technologies and materials by OLED manufacturers, and their continued willingness to utilize our OLED technologies and materials;



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the comparative advantages and disadvantages of our OLED technologies and materials versus competing technologies and materials currently on the market;



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the nature and potential advantages of any competing technologies that may be developed in the future;



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our ability to compete against third parties with resources greater than ours;



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our ability to maintain and improve our competitive position following the expiration of our fundamental OLED patents;



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the adequacy of protections afforded to us by the patents that we own or license and the cost to us of maintaining, enforcing and defending those patents;



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our ability to obtain, expand and maintain patent protection in the future, and to protect our non patented intellectual property;



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our exposure to and ability to withstand third-party claims and challenges to our patents and other intellectual property rights;



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the payments that we expect to receive under our existing contracts with OLED manufacturers and the terms of contracts that we expect to enter into with OLED manufacturers in the future;



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our future capital requirements and our ability to obtain additional financing if and when needed;

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our future OLED technology licensing and OLED material revenues and results of operations; and



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general economic and market conditions.

        Changes or developments in any of these areas could affect our financial results or results of operations, and could cause actual results to differ materially from those contemplated by any forward-looking statements.

        All forward looking statements speak only as of the date of this prospectus or the documents incorporated by reference, as the case may be. We do not undertake any duty to update any of these forward-looking statements to reflect events or circumstances after the date of this prospectus, or to reflect the occurrence of unanticipated events.

OUR COMPANY

        We are a leader in the research, development and commercialization of organic light emitting diode, or OLED, technologies and materials. OLEDs are thin, lightweight and power-efficient solid-state devices that emit light, making them highly suitable for use in full-color displays and as lighting products. OLED displays are capturing a growing share of the flat panel display market. We believe that this is because OLEDs offer potential advantages over competing display technologies with respect to power efficiency, contrast ratio, viewing angle, video response time and manufacturing cost. We also believe that OLED lighting products have the potential to replace many existing light sources in the future because of their high power efficiency, excellent color rendering index, low heat generation and novel form factor. Our technology leadership and intellectual property position should enable us to share in the revenues from OLED displays and lighting products as they enter mainstream consumer and other markets.

        Our primary business strategy is to further develop and license our proprietary OLED technologies to manufacturers of products for display applications, such as cell phones, portable media devices, tablets, laptop computers and televisions, and specialty and general lighting products. In support of this objective, we also develop new OLED materials and sell materials to those product manufacturers. Through our internal research and development efforts and our relationships with world-class partners such as Princeton University, the University of Southern California, the University of Michigan, Motorola Solutions, Inc. and PPG Industries, Inc., we have established a significant portfolio of proprietary OLED technologies and materials. We currently own, exclusively license or have the sole right to sublicense more than 1,000 patents issued and pending worldwide.

        We sell our proprietary OLED materials to customers for evaluation and use in commercial OLED products. We also enter into agreements with manufacturers of OLED display and lighting products under which we grant them licenses to practice under our patents and to use our proprietary know-how. At the same time, we work with these and other companies who are evaluating our OLED technologies and materials for possible use in commercial OLED display and lighting products.

Corporate Information

        Our corporation was organized under the laws of the Commonwealth of Pennsylvania in April 1985. Our business was commenced in June 1994 by a company then known as Universal Display Corporation, which had been incorporated under the laws of the State of New Jersey. On June 22, 1995, a wholly-owned subsidiary of ours merged into this New Jersey corporation. The surviving corporation in this merger became a wholly-owned subsidiary of ours and changed its name to UDC, Inc. Simultaneously with the consummation of this merger, we changed our name to Universal Display Corporation. UDC, Inc. now functions as an operating subsidiary of ours and has overlapping officers and directors. We have also formed other wholly-owned subsidiaries, including Universal

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Display Corporation Hong Kong, Ltd. (2008), Universal Display Corporation Korea, Inc. (2010) and Universal Display Corporation Japan, K.K. (2011).

        Our principal executive offices are located at 375 Phillips Boulevard, Ewing, New Jersey 08618 and our telephone number is (609) 671-0980. Our Internet address is www.universaldisplay.com. The information on our Internet site is not part of this prospectus.

RISK FACTORS

        An investment in our securities involves a high degree of risk. Before purchasing our securities, you should carefully consider the risks described in the SEC filings incorporated by reference in this prospectus, including, without limitation, the Annual Report on Form 10-K for the year ended December 31, 2010. You should not purchase our securities if you cannot afford the loss of your entire investment.

THE OFFERING

        Using this prospectus, we may offer from time to time, in one or more series, together or separately, at prices and on terms to be determined at the time of offering, shares of our common stock, $0.01 par value.

USE OF PROCEEDS

        Unless otherwise provided in the applicable prospectus supplement accompanying this prospectus, the net proceeds, if any, from the sale of the securities offered hereby will be used for general corporate purposes, including the acquisition or development of properties, assets, entities or technologies, and the repayment of indebtedness. As of the date of this prospectus, we have not identified as probable any specific material proposed uses of these proceeds. If, as of the date of any prospectus supplement, we have identified any such uses, we will describe them in the prospectus supplement. The amount of securities offered from time to time pursuant to this prospectus and any prospectus supplement, and the precise amount of the net proceeds we will receive from the sale of such securities, as well as the timing of receipt of those proceeds, will depend upon our funding requirements. If we elect at the time of an issuance of securities to make different or more specific uses of the proceeds than as set forth herein, we will describe those uses in the applicable prospectus supplement.

PLAN OF DISTRIBUTION

        We may sell the securities being offered hereby: (a) directly to purchasers; (b) through agents; (c) through underwriters; (d) through dealers; or (e) through a combination of any such methods of sale.

        The distribution of the securities may be effected from time to time in one or more transactions:

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at a fixed price or at final prices, which may be changed;



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at market prices prevailing at the time of sale;



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at prices related to such prevailing market prices; or



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at negotiated prices.

        Offers to purchase securities may be solicited directly by us, or by agents designated by us, from time to time. Any such agent, which may be deemed to be an underwriter as that term is defined in the Securities Act of 1933, as amended (the "Securities Act"), involved in the offer or sale of the securities in respect of which this prospectus is delivered will be named, and any commissions payable by us to such agent will be set forth, in the applicable prospectus supplement.

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        If an underwriter is, or underwriters are, utilized in the offer and sale of securities in respect of which this prospectus and the accompanying prospectus supplement are delivered, we will execute an underwriting agreement with such underwriter(s) for the sale to it or them and the name(s) of the underwriter(s) and the terms of the transaction, including any underwriting discounts and other items constituting compensation of the underwriters and dealers, if any, will be set forth in such prospectus supplement, which will be used by the underwriter(s) to make resales of the securities in respect of which this prospectus and such prospectus supplement are delivered to the public. The securities will be acquired by the underwriters for their own accounts and may be resold from time to time in one or more transactions, including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

        If a dealer is utilized in the sale of the securities in respect of which this prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale. The name of the dealer and the terms of the transaction will be identified in the applicable prospectus supplement.

        If an agent is used in an offering of securities being offered by this prospectus, the agent will be named, and the terms of the agency will be described, in the applicable prospectus supplement relating to the offering. Unless otherwise indicated in the prospectus supplement, an agent will act on a best efforts basis for the period of its appointment.

        If indicated in the applicable prospectus supplement, we will authorize underwriters or their other agents to solicit offers by certain institutional investors to purchase securities from us pursuant to contracts providing for payment and delivery at a future date. Institutional investors with which these contracts may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and others. In all cases, these purchasers must be approved by us. The obligations of any purchaser under any of these contracts will not be subject to any conditions except that (a) the purchase of the securities must not at the time of delivery be prohibited under the laws of any jurisdiction to which that purchaser is subject, and (b) if the securities are also being sold to underwriters, we must have sold to these underwriters the securities not subject to delayed delivery. Underwriters and other agents will not have any responsibility in respect of the validity or performance of these contracts.

        Certain of the underwriters, dealers or agents utilized by us in any offering hereby may be customers of, including borrowers from, engage in transactions with, and perform services for us or one or more of our affiliates in the ordinary course of business. Underwriters, dealers, agents and other persons may be entitled, under agreements which may be entered into with us, to indemnification against certain civil liabilities, including liabilities under the Securities Act of 1933, as amended.

        Until the distribution of the securities is completed, rules of the SEC may limit the ability of the underwriters and certain selling group members, if any, to bid for and purchase the securities. As an exception to these rules, the representatives of the underwriters, if any, are permitted to engage in certain transactions that stabilize the price of the securities. Such transactions may consist of bids or purchases for the purpose of pegging, fixing or maintaining the price of the securities.

        If underwriters create a short position in the securities in connection with the offering thereof (in other words, if they sell more securities than are set forth on the cover page of the applicable prospectus supplement), the representatives of such underwriters may reduce that short position by purchasing securities in the open market. Any such representatives also may elect to reduce any short position by exercising all or part of any over-allotment option described in the applicable prospectus supplement.

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        Any such representatives also may impose a penalty bid on certain underwriters and selling group members. This means that if the representatives purchase securities in the open market to reduce the underwriters' short position or to stabilize the price of the securities, they may reclaim the amount of the selling concession from the underwriters and selling group members who sold those shares as part of the offering thereof.

        In general, purchases of a security for the purpose of stabilization or to reduce a syndicate short position could cause the price of the security to be higher than it might otherwise be in the absence of such purchases. The imposition of a penalty bid might have an effect on the price of a security to the extent that it were to discourage resales of the security by purchasers in the offering.

        Neither we nor any of the underwriters, if any, makes any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the securities. In addition, neither we nor any of the underwriters, if any, makes any representation that the representatives of the underwriters, if any, will engage in such transactions or that such transactions, once commenced, will not be discontinued without notice.

        The anticipated date of delivery of the securities offered by this prospectus will be described in the applicable prospectus supplement relating to the offering. The securities offered by this prospectus may or may not be listed on a national securities exchange or a foreign securities exchange. We cannot give any assurances that there will be a market for any of the securities offered by this prospectus and any prospectus supplement.

        We estimate that the total expenses we will incur in offering the securities to which this prospectus relates, excluding underwriting discounts and commissions, if any, will be approximately $400,000.

ABOUT THIS PROSPECTUS

        This prospectus describes certain securities of Universal Display Corporation, a Pennsylvania corporation. We sometimes refer to Universal Display Corporation, together with its subsidiaries, using the words "we," "our" or "us," or as the "Company." This prospectus is part of a registration statement that we filed with the SEC utilizing a "shelf" registration process, which allows us to offer and sell any combination of the securities described in this prospectus in one or more offerings. Using this prospectus, we may offer an unlimited amount of our common stock.

        This prospectus contains a general description of the securities we may offer. We will describe the specific terms of these securities, as necessary, in supplements that we attach to this prospectus for each offering. Each supplement will also contain specific information about the terms of the offering it describes. The supplements may also add, update or change information contained in this prospectus. In addition, as we describe below in the section entitled "Where You Can Find More Information," we have filed and plan to continue to file other documents with the SEC that contain information about us. Before you decide whether to invest in our securities, you should read this prospectus, the supplement that further describes the offering of those securities and the information we otherwise file with the SEC.

WHERE YOU CAN FIND MORE INFORMATION

        We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended. Therefore, we file reports, proxy statements and other information with, and furnish other reports to, the SEC. You can read and copy all of these documents at the SEC's public reference room located at 100 F Street, N.E., Washington, D.C. 20549. You may obtain information on the operation of the SEC's public reference facilities by calling the SEC at 1-800-SEC-0330. You can also read and copy all of the above-referenced documents at the offices of the NASDAQ Global Market, 1735 K Street N.W., Washington, D.C. 20006. You also may obtain the documents we file with the SEC from the SEC's Web site on the Internet that is located at http://www.sec.gov.

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        We "incorporate by reference" in this prospectus the information we file with the SEC, which means that we can disclose important information to you by referring you to another document we file with the SEC. The information incorporated by reference in this prospectus is an important part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference in this prospectus the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, including filings made after the date of this prospectus but before the end of this offering. The documents that we are incorporating by reference are:

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Our Annual Report on Form 10-K for the year ended December 31, 2010;



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Our Current Reports on Form 8-K filed with the SEC on January 6, 2011, February 7, 2011, March 8, 2011, March 10, 2011 and March 21, 2011;



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Our Definitive Proxy Statement for our 2010 Annual Meeting of Shareholders, filed with the SEC on April 26, 2010; and



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The description of our common stock that is contained in our Registration Statement on Form 8-A filed with the SEC on August 6, 1996.

        You should read the information relating to us in this prospectus, together with the information in the documents incorporated by reference in this prospectus.

        Any statement contained in a document incorporated by reference in this prospectus, unless otherwise indicated in that document, speaks as of the date of the document. Statements contained in this prospectus may modify or replace statements contained in the documents incorporated by reference. In addition, some of the statements contained in one or more of the documents incorporated by reference may be modified or replaced by statements contained in a document incorporated by reference that is filed thereafter.

        You may request a copy of any or all of these filings, at no cost, by writing or telephoning us at Universal Display Corporation, 375 Phillips Boulevard, Ewing, New Jersey 08618, Attention: Corporate Secretary, Telephone: (609) 671-0980.

LEGAL OPINION

        Morgan, Lewis & Bockius LLP, Philadelphia, Pennsylvania, will pass on the validity of the securities that may be offered by the prospectus.

EXPERTS

        The consolidated financial statements of Universal Display Corporation and subsidiaries as of December 31, 2010 and 2009, and for each of the years in the three-year period ended December 31, 2010, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2010, have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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5,000,000 Shares

Common Stock

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Goldman, Sachs & Co.

UBS Investment Bank

Canaccord Genuity
Cowen and Company
Needham & Company, LLC
Oppenheimer & Co.

Avian Securities, LLC
Davenport & Company LLC
Fagenson & Co., Inc.

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