A multinational investigation is a law-enforcement case carried out across more than one country. It is used when suspects, servers, payments, victims, or evidence are spread across borders, so no single agency can handle the full case alone. Investigators may share intelligence, coordinate warrants, preserve logs, and align arrests or seizures under different legal systems.
In cyber security, these investigations matter because modern attacks are rarely confined to one jurisdiction. Ransomware crews, phishing networks, botnets, and money-laundering pipelines often use international infrastructure and victims in multiple regions. Coordinated investigations can disrupt command-and-control servers, recover digital evidence, and identify operators, but they also require careful attribution and legal review. For defenders, the term signals that a case may involve shared intelligence and broader enforcement pressure, not just a local criminal complaint.