# Persistent Identifier A persistent identifier is an identifier whose evidentiary value depends on which stage assigns it, its scope, and which operations preserve or destroy it. ## Persistence and scope Persistence answers how long an identifier survives. Scope answers where it is unique. An inode may survive rename but not copy and is unique only within a filesystem; an eMMC CID survives an operating-system reinstall; a serial or regulatory identifier may survive for the physical life of the object. ## Archival rule Every identifier record should state: - assigning stage and authority; - uniqueness scope; - operations it survives; - known collision risks; - time and method of observation. ## Source [[Index - Stages of Interception#Cross-stage properties|Stages of Interception — Cross-stage properties]] · [[Identifier Collision]] · [[Canonical Machine Identifiers]].