Why it matters
Classification only works if people can tell what they're looking at without asking.
How a self-led small team implements it
A footer or filename convention (e.g. "[Confidential]") is a legitimate labelling scheme for a small team.
What auditors expect to see
Sample labeled documents, labelling guideline.
Track A.5.13 in your own Statement of Applicability — mark it applicable, log your justification, and link it to the risk that drove it.
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