Passguard is a Dutch stealer intelligence platform founded in 2021 that specializes in detecting and responding to infostealer malware infections. The company monitors criminal marketplaces on the dark web and Telegram channels where stolen data from compromised devices is traded, providing organizations with visibility into infections that traditional security tools often miss. The platform gives security teams access to data from compromised devices, including stolen credentials, active sessions, and cookies. This enables organizations to identify infected devices, revoke compromised sessions, and prevent unauthorized access before attackers can exploit the stolen information. Passguard focuses on detecting infections on both managed and unmanaged devices, including BYOD endpoints and contractor systems that typically fall outside traditional EDR coverage. The platform operates through a straightforward process: organizations share their domains for monitoring, Passguard continuously scans stealer marketplaces for infected devices with sessions in those systems, and alerts are sent when compromises are detected. The system organizes data into employee infections, user infections, and infection traces, with collaboration features that allow teams to add labels, comment on alerts, and track investigation status. Passguard serves organizations across energy, manufacturing, infrastructure, healthcare, and technology sectors, monitoring infostealer risks for hundreds of thousands of employees across three continents. The founding team includes specialists with backgrounds in intelligence, law enforcement, and digital investigations.