X0508 4 2023-08-11 0 0001692819 Vistra Corp. VST 0001703634 Moore Stephanie Zapata 6555 SIERRA DRIVE IRVING TX 75039 0 1 0 0 EVP and General Counsel 0 Common Stock 2023-08-11 4 M 0 85534 19.68 A 223316 D Common Stock 2023-08-11 4 S 0 85534 30.553 D 137782 D Common Stock 2023-08-11 4 M 0 37128 18.90 A 174910 D Common Stock 2023-08-11 4 S 0 37128 30.60 D 137782 D Common Stock 2023-08-14 4 M 0 107466 19.68 A 245248 D Common Stock 2023-08-14 4 S 0 107466 30.216 D 137782 D 2018 Employee Stock Option (right to buy) 19.68 2023-08-11 4 M 0 85534 0.00 D 2023-04-09 2027-04-09 Common Stock 85534 107466 D 2017 Employee Stock Option (right to buy) 18.90 2023-08-11 4 M 0 37128 0.00 D 2021-03-31 2028-03-31 Common Stock 37128 0 D 2018 Employee Stock Option (right to buy) 19.68 2023-08-14 4 M 0 107466 0.00 D 2023-04-09 2027-04-09 Common Stock 107466 0 D Represents a weighted-average price. These shares were sold in multiple transactions at prices ranging from $30.25 to $30.85, inclusive. For all transactions reported in this Form 4 utilizing a weighted-average price, the reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. Represents a weighted-average price. These shares were sold in multiple transactions at prices ranging from $30.50 to $30.76, inclusive. For all transactions reported in this Form 4 utilizing a weighted-average price, the reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. Represents a weighted-average price. These shares were sold in multiple transactions at prices ranging from $30.09 to $30.33, inclusive. For all transactions reported in this Form 4 utilizing a weighted-average price, the reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, information regarding the number of shares sold at each price within the range. The 2018 employee stock options vested in two equal installments beginning April 9, 2022. This reflects an upward adjustment of 110 shares to include options granted in 2018 that were omitted from the Form 4 filed April 5, 2019 (and subsequent Forms 4s) due to a clerical error. The 2017 employee stock options vested in three equal installments beginning March 31, 2019. /s/ Yuki Whitmire, as Attorney-in-Fact 2023-08-15