While ransomware grabs headlines, business email compromise (BEC) quietly causes billions in losses every year. For private sector responders, these cases present unique investigative hurdles: social engineering, subtle logins, wire transfers, and abuse of legitimate SaaS features. This presentation dives into the forensic artifacts and investigative playbooks for BEC cases, including Office 365 sign-in logs, forwarding rules, OAuth abuse, and transaction metadata. We’ll explore how to triage compromised accounts, correlate access patterns with financial events, and present findings in a way that supports both containment and legal/regulatory needs. Whether you work in corporate IR, legal, or compliance, this session will equip you with the tools to tackle one of the most common—and costly—forms of corporate compromise.