X0306 4 2020-02-28 0 0001580156 Houghton Mifflin Harcourt Co HMHC 0001585194 Bayers William Frederick C/O HOUGHTON MIFFLIN HARCOURT CO., 125 HIGH STREET BOSTON MA 02110 0 1 0 0 See remarks. Common Stock 2020-02-28 4 M 0 9654 0.00 A 49883 D Common Stock 2020-02-28 4 F 0 4799 5.47 D 45084 D Common Stock 2020-02-28 4 M 0 11336 0.00 A 56420 D Common Stock 2020-02-28 4 F 0 5127 5.47 D 51293 D Restricted Stock Units 2020-02-28 4 M 0 9654 0.00 D Common Stock 9654 0 D 9,654 restricted stock units held by Mr. Bayers vested on February 28, 2020 and were settled in exchange for a like amount of shares of Houghton Mifflin Harcourt Company's (the "Company") common stock, subject to the Company's withholding of 4,799 shares of common stock to satisfy withholding obligations in connection with federal, state, local or other taxes required to be withheld or paid in connection with the settlement of the restricted stock units. 11,336 performance stock units held by Mr. Abbott vested on February 28, 2020 and were settled in exchange for a like amount of shares of the Company's common stock, subject to the Company's withholding of 5,127 shares of common stock to satisfy withholding obligations in connection with federal, state, local or other taxes required to be withheld or paid in connection with the settlement of the performance stock units. Each restricted stock unit represents a contingent right to receive one share of the Company's common stock. Executive Vice President, Secretary and General Counsel. /s/ William F. Bayers 2020-03-03