X0306 4 2019-11-01 0 0001013857 PEGASYSTEMS INC PEGA 0001480560 Trefler Leon C/O PEGASYSTEMS INC. 1 ROGERS STREET CAMBRIDGE MA 02142 0 1 0 0 SVP, Global Customer Success Common Stock 2019-11-01 4 M 0 1473 20.05 A 9121 D Common Stock 2019-11-01 4 F 0 873 75.21 D 8248 D Common Stock 2019-11-01 4 S 0 600 76.16 D 7648 D Stock Options 20.05 2019-11-01 4 M 0 1473 0.00 D 2015-03-07 2024-03-07 Common Stock 1473 24553 D Represents the exercise price of the stock options referenced in Table II and Mr. Trefler's tax liability, which were paid by way of the Company withholding shares of equal value. Sold pursuant to a pre-arranged stock trading plan under rule 10b5-1 of the Securities Exchange Act of 1934, as amended. Represents the weighted average of the sale prices on November 1, 2019, ranging from $76.03 to $76.25. The individual has provided the Company, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Company, upon request, full information regarding the number of shares sold at each separate price. Does not include shares of common stock subject to unvested restricted stock units and/or options awards. Options vested 20% on March 7, 2015, with the remaining 80% vesting in equal quarterly installments over the next four years. The grant of stock options was previously reported as 13,013, but has been adjusted to reflect a 2-for-1 stock split that occurred on April 1, 2014. /s/ Janet Mesrobian, Esq., Attorney-in-Fact for Leon Trefler 2019-11-05