X0306 4 2021-06-15 0 0000715579 ACNB CORP ACNB 0001710898 Seibel Donald Arthur Jr 16 LINCOLN SQUARE GETTYSBURG PA 17325 1 0 0 0 ACNB Corporation Common 2021-06-15 2021-06-17 4 A 0 101.6979 28.27 A 19476.6466 D ACNB Corporation Common 10910.2604 I Trust The date of execution was determined in accordance with SEC Rule 16a-3(g)(2) and (g)(4). The shares represent stock received in lieu of director fees pursuant to a plan. The amount of securities beneficially owned includes 22.846480 shares of common stock purchased for the same Transaction Date of June 15, 2021, through the automatic reinvestment of dividends under the ACNB Corporation Dividend Reinvestment and Stock Purchase Plan, which are exempt from the reporting requirements of Section 16 of the Securities Exchange Act of 1934. The amount of securities beneficially owned includes 103.215423 shares of common stock purchased for the same Transaction Date of June 15, 2021, through the automatic reinvestment of dividends under the ACNB Corporation Dividend Reinvestment and Stock Purchase Plan, which are exempt from the reporting requirements of Section 16 of the Securities Exchange Act of 1934. /s/ Lynda L. Glass as POA for Donald Arthur Seibel, Jr. 2021-06-21