Auditing file access and sharing involves systematically tracking and reviewing who accesses files or folders, when they accessed them, what actions they performed (like view, edit, copy, download, share), and with whom they were shared. This goes beyond simply seeing who owns a file; it monitors interactions and permissions changes over time. Typically enabled through centralized logging features in operating systems, file servers, or cloud storage platforms, it creates an activity trail.

Common applications include ensuring regulatory compliance (like HIPAA for patient records in healthcare or GDPR for personal data in finance) by demonstrating who accessed sensitive information. IT departments also use these logs for security incident response, investigating potential data breaches, unauthorized sharing, or unusual file activity patterns. Tools often providing these capabilities are Microsoft Windows Server auditing, Unix/Linux auditd, AWS CloudTrail for S3, Azure Activity Logs, Microsoft 365 audit logs, Google Workspace audit logs, and enterprise file sharing solutions like Box or Dropbox.

Robust auditing enhances security accountability, aids compliance evidence gathering, and deters misuse. However, limitations exist: complex log management, potential performance overhead, the need for careful data retention policies, and the inability to prevent deliberate malicious actions by authorized users. Proper configuration and regular log review are essential for auditing to be effective; when implemented well, it significantly strengthens data governance and incident detection capabilities.