A term meaning to strike or delete; it is used in this book in relation to an entry on the copyright or other intellectual property (e.g., ICT) register. The CIPO can expunge entries in limited specified circumstances — for example, for a clerical error. More usually, the Federal Court exercises this power. Expungement invalidates the right as against the world, not merely the parties to the litigation. An entry may also be amended, corrected, or rectified, a lesser remedy than expungement, which changes, but does not delete, the entry.