Sec Form 4 Filing - ROSENBLATT SIDNEY D @ UNIVERSAL DISPLAY CORP \PA\ - 2021-04-06

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person ROSENBLATT SIDNEY D 2. Issuer Name and Ticker or Trading Symbol UNIVERSAL DISPLAY CORP \PA\ [ OLED] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) EVP and CFO (Last) (First) (Middle) C/O UNIVERSAL DISPLAY CORPORATION, 375 PHILLIPS BLVD. 3. Date of Earliest Transaction (MM/DD/YY) 04/06/2021 (Street) EWING, NJ08618 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 04/06/2021 A 1,487 ( 1 ) A $ 0 153,833 ( 2 ) D Common Stock 04/06/2021 F 630 ( 3 ) D $ 242.1 153,203 D Common Stock 92,275 I By Grantor Retained Annuity Trust Common Stock 13,000 I By Spouse

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other ROSENBLATT SIDNEY D C/O UNIVERSAL DISPLAY CORPORATION 375 PHILLIPS BLVD. EWING, NJ08618 X EVP and CFO Signatures /s/ Sidney. D. Rosenblatt (by Mauro Premutico as power of attorney) 04/08/2021 Signature of Reporting Person Date

Explanation of Responses:

( 1 )These shares were granted to Mr. Rosenblatt as performance units under the Company's Long Term Incentive Plan as part of his 2018 compensation and vested subject to the satisfaction of certain performance conditions, which our Human Capital Committee certified on April 6, 2021 as having occurred. ( 2 )Includes 10 shares acquired under the Universal Display Corporation Employee Stock Purchase Plan on March 31, 2021. ( 3 )These shares were withheld to satisfy a tax liability in connection with the vesting on April 6, 2021 of 1,487 shares of restricted stock previously granted to Mr. Rosenblatt.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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