X0306 4 2022-04-07 1 0001580156 Houghton Mifflin Harcourt Co HMHC 0001129822 MCKERNAN JOHN R JR C/O HOUGHTON MIFFLIN HARCOURT CO. 125 HIGH STREET BOSTON MA 02110 1 0 0 0 Common Stock 2022-04-07 4 D 0 30429 D 0 D Restricted Stock Unit 2022-04-07 4 D 0 11066 D Common Stock 11066 0 D Phantom Stock 2022-04-07 4 D 0 94952 D Common Stock 94952 0 D In connection with that certain Agreement and Plan of Merger by and among Houghton Mifflin Harcourt Company (the "Company"), Harbor Purchaser Inc., and Harbor Holding Corp., dated as of February 21, 2022 (the "Merger Agreement") and the related tender offer, the Reporting Person became entitled to receive, in respect of each share of the Company's common stock, an amount in cash equal to $21.00. Each restricted stock unit ("RSU") represented the economic equivalent of one share of the Company's common stock. Pursuant to the terms of the Merger Agreement, immediately prior to the Acceptance Time (as defined in the Merger Agreement), each RSU that was outstanding and unvested vested in full and was cancelled, and the Reporting Person became entitled to receive, in respect of each share of common stock subject to such RSU, an amount in cash equal to $21.00. Each share of phantom stock represents a contingent right to receive one share of the Company's common stock. Pursuant to the terms of the Company's Non-Employee Director Deferred Compensation Plan (the "Deferred Compensation Plan"), the phantom stock is to be distributed following the occurrence of a Change in Control (as defined in the Deferred Compensation Plan), which includes the transaction contemplated by the Merger Agreement. The Reporting Person became entitled to receive, in respect of each share of common stock subject to such phantom stock, an amount in cash equal to $21.00. William F. Bayers is the Executive Vice President, Secretary and General Counsel of the Company. s/ William F. Bayers, Attorney-in-Fact 2022-04-11