X0306 4 2020-03-18 0001005284 UNIVERSAL DISPLAY CORP \PA\ OLED 0001192994 HARTLEY C KEITH C/O UNIVERSAL DISPLAY CORPORATION 375 PHILLIPS BLVD. EWING NJ 08618 1 0 0 0 Common Stock 2020-03-18 4 S 0 128 106.11 D 91360 D Represents the weighted average of a range of sale prices per share from $105.57 to $106.24. The reporting person undertakes to provide to the staff of the Securities and Exchange Commission, the Company or any shareholder of the Company, upon request, full information regarding the number of shares sold at each seperate price. /s/ C. Keith Hartley (by Mauro Premutico as power of attorney) 2020-03-20