Macmillan and its affiliates reported a cybersecurity incident occurring between June 16 and June 25, 2022. The incident involved suspicious activity resulting in the encryption of files (ransomware) and unauthorized access to systems. Personal information, including names, was exfiltrated. Macmillan engaged third-party specialists, notified federal law enforcement, and offered 24 months of credit monitoring and identity restoration services to affected individuals across multiple US jurisdictions.