Article 50 applies from today. Most teams will treat this as a labelling task. The harder problem begins after publication. The file gets resized. Metadata disappears. A different version is reposted. The asset moves from one platform to another. The person reviewing it no longer has the original context. At that point, the question is no longer just whether the right disclosure appeared on day one. It is whether someone can still identify the asset and inspect its history later. That is the provenance gap. Numbers gives the asset a persistent reference, a proof path, and a record that remains checkable after the handoff. Transparency starts with marking and disclosure. Accountability starts when the record survives.