Sherwin Seligsohn, the founder and chairman of Universal Display Corp. (“UDC”; NASDAQ: OLED) sold more than $900,000 worth of stock on Nov. 8th, according to a Form 4 filed today with the Securities and Exchange Commission. Seligsohn chose to exercise stock options months before their January expiration and then to immediately sell the bulk of the shares, according to the Form 4. We believe this type of insider selling is a clear negative signal to UDC shareholders.