X0508 4 2026-02-17 0 0001013857 PEGASYSTEMS INC PEGA 0001032235 TREFLER ALAN C/O PEGASYSTEMS INC. 225 WYMAN STREET, STE 300 WALTHAM MA 02451 1 1 1 0 C.E.O. & Chairman 1 Common stock 2026-02-17 4 S 0 11742 45.12 D 44337712 D Common stock 2026-02-18 4 S 0 17930 45.03 D 44319782 D Common stock 8703426 I Alan N. Trefler Grantor Retained Annuity Trust II of 2024 Common stock 2071585 I The Trefler 2025 Trust Common stock 10879283 I Alan N. Trefler Grantor Retained Annuity Trust I of 2024 Common stock 10876525 I Alan N. Trefler Irrevocable Non-GST Trust of 2022 Sold pursuant to a pre-arranged trading plan adopted by Mr. Trefler on November 11, 2025 under Rule 10b5-1 of the Securities Exchange Act of 1934, as amended. Represents the weighted average of sale prices, ranging from $45.00 to $45.37. The individual has provided the Company, and undertakes to provide to the staff of the Security and Exchange Commission or any security holder of the Company, upon request, full information regarding the number of shares sold at each separate price. Represents the weighted average of sale prices, ranging from $45.00 to $45.26. The individual has provided the Company, and undertakes to provide to the staff of the Security and Exchange Commission or any security holder of the Company, upon request, full information regarding the number of shares sold at each separate price. /s/ Ewelina Kemp, Attorney-in-Fact for Alan Trefler 2026-02-19