UNIVERSAL DISPLAY CORP \PA\

Trading Arrangements

During the quarter ended September 30, 2026, none of our directors or executive officers adopted orterminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K.

SERP Amendment

On October 27, 2026, the Company’s Board of Directors (the “Board”), on the recommendation of its Human Capital Committee (the “HCC”), adopted Amendment 2026-1 to the SERP (“Amendment 2026-1”). Amendment 2026-1 amended the SERP to change the designated retirement age from age 65 to age 62, and to provide that persons who are at least age 62 but less than age 65 at the time of their qualifying termination or death, and who have at least 15 but less than 20 years of service, will receive prorated benefits as described in Amendment 2026-1. This change affects only one named executive officer participant in the SERP, Mauro Premutico, the Company’s Senior Vice President, Planning, Chief Legal Officer and Secretary, as all other named executive officer participants in the SERP are at least age 65.

Senior Management Severance Program

Also on October 27, 2026, the Board adopted a Senior Management Severance Program (the “SMSP”). Participants in the SERP are not eligible to participate in the SMSP. Thus, the only named executive officer who will participate in the SMSP is Brian Millard, the Company’s Vice President, Chief Financial Officer and Treasurer. Participants in the SMSP are entitled to receive, following termination without cause, including a termination for good reason (both as defined in the SMSP), amounts including the following: (i) earned salary through the termination date; (ii) accrued but unpaid bonus for a completed year; (iii) a severance payment equal to twelve months of base salary plus the full year bonus that would have been earned for the year in which termination occurs based on actual performance as measured at the conclusion of the applicable year. The SMSP benefits shall not duplicate any payments to which the executive may become entitled under the executive’s change in control agreement. The benefits specified in clauses (ii) and (iii) above will vest 25%/year over four years, with the Board having the discretion to accelerate upon a separation event.