X0306 4 2022-03-17 0000944695 HANOVER INSURANCE GROUP, INC. THG 0001428157 Roche John C C/O THE HANOVER INSURANCE GROUP, INC. 440 LINCOLN STREET WORCESTER MA 01653 1 1 0 0 President and CEO Common Stock 2022-03-17 4 M 0 7258 40.01 A 81993.524 D Common Stock 2022-03-17 4 S 0 6193 145.651 D 75800.524 D Common Stock 2022-03-17 4 S 0 1065 146.2091 D 74735.524 D Common Stock Option (right to buy) 40.01 2022-03-17 4 M 0 7258 0 D 2023-02-26 Common Stock 7258 14516 D Exercise of options scheduled to expire in February 2023 and resulting sale of shares reported were effected pursuant to a pre-established Rule 10b5-1 Trading Plan. The price reported in Column 4 is a weighted average price. The shares were sold at multiple prices ranging from $145.02 to $146.00. The Reporting Person undertakes to provide The Hanover Insurance Group, Inc. ("THG"), any security holder of THG, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. The price reported in Column 4 is a weighted average price. The shares were sold at multiple prices ranging from $146.035 to $146.50. The Reporting Person undertakes to provide THG, any security holder of THG, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. Does not include 7,652 shares held indirectly by the Reporting Person's spouse. The option, representing the right to purchase a total of 21,774 shares, vested 1/3 on each of 2/26/14, 2/26/15 and 2/26/16, and is scheduled to expire on 2/26/2023. /s/ Matthew R. Frascella pursuant to Confirming Statement 2022-03-21