Custodian
The person or unit responsible for holding and maintaining particular records — and, in e-discovery, an individual whose records may contain information relevant to a matter.
A custodian is the person or organizational unit responsible for holding and maintaining particular records. In records management, identifying the custodian establishes accountability for a record series and is part of maintaining a clear chain of custody.
The term has a specific, important meaning in e-discovery: a custodian is an individual whose files, email, and devices may hold ESI relevant to a matter. When litigation is anticipated, the first steps include identifying custodians and issuing them a litigation hold directing them to preserve relevant records. Knowing who the custodians are — and what records they hold — is essential to both everyday recordkeeping accountability and defensible preservation when a dispute arises.