HMH (hmhco.com) — Ransomware Incident Claimed by ShinyHunters
- Victim: HMH (hmhco.com)
- Claimed by ShinyHunters
- Date claimed: 2025-10-03
- Country: US
- Sector: Education
HMH, or Houghton Mifflin Harcourt, is a long-established publishing company specializing in educational content. They provide a variety of instructional technology, assessments, and other learning materials to schools in over 150 countries. The company also publishes a number of well-known trade and reference works, alongside children's books.