X0306 4 2018-03-08 0 0001379895 DYNEGY INC. DYN 0001620424 Cox Julius 601 TRAVIS STREET SUITE 1400 HOUSTON TX 77002 0 1 0 0 EVP Common Stock 2018-03-08 4 M 0 5543 A 43480 D Common Stock 2018-03-08 4 F 0 2180 13.47 D 41300 D Restricted Stock Units 2018-03-08 4 M 0 5543 0.00 D Common Stock 5543 60084 D Each restricted stock unit is the economic equivalent of one share of Dynegy Inc. common stock. These restricted stock units were withheld to pay the taxes applicable to the vesting of 5,543 units of restricted stock on March 8, 2018. Reflects closing stock price on March 8, 2018. Amount includes 15,711 restricted stock units that vest in two annual equal installments beginning on March 1, 2019. On March 8, 2016, the reporting person was granted 16,629 restricted stock units representing the contingent right to receive for each restricted stock unit one share of Dynegy Inc. common stock or the cash equivalent of one share of common stock. The restricted stock units vest in three annual equal installments which began on March 8, 2017. /s/ Heidi D. Lewis, Attorney-in-Fact 2018-03-12