X0306 4 2018-03-01 0 0001379895 DYNEGY INC. DYN 0001530677 James Catherine C. 601 TRAVIS 14TH FLOOR HOUSTON TX 77002 0 1 0 0 Exec VP and General Counsel Common Stock 2018-03-01 4 F 0 4666 12.34 D 88698 D These restricted stock units were withheld by Issuer to pay the taxes applicable to the vesting of 12,365 units of restricted stock on March 1, 2018. Reflects the closing stock price on March 1, 2018. Amount includes 3,854 restricted stock units that vest on March 3, 2018 and 24,730 restricted stock units that vest in two annual equal installments beginning on March 1, 2019. /s/ Heidi D. Lewis, Attorney-in-Fact 2018-03-05