HMH(HMH) - Prospectus(update)

As filed with the Securities and Exchange Commission on March 18, 2026. Registration No. 333-281497 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 HMH Holding Inc. (Exact name of registrant as specified in its charter) (State or other jurisdiction of incorporation or organization) Delaware 3533 99-2746883 (Primary Standard Industrial Classification Code Number) 3300 North Sam Houston Parkway East (I.R.S. Employer Identification Number) Houston, Texas 77032 (281) 449-2000 (Address, i ...