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The verification clause opens by stating that the verifying entity acquires the data items the process needs. It is a short general subclause, and its value is procedural: it separates the retrieval of the inputs from the checks on them, so that a reader can see what has to be in hand before any arithmetic starts.

What it asks

Record which data items the verifier needs, where each one comes from and what bounds it. The key, the witness and the second part come from the signed message or the protocol. The curve parameters and the base point come from the named set. If any item is fetched from a directory, record the trust anchor for it.

What the amendment does

Inserts 6.13.5.1. So this is new text rather than a change to wording.

Who it binds

The verifier owner and the integration owner.

Evidence an auditor samples

• The verifier input list, one row per item with its source and bound (interface specification)
• The configuration that pins the parameter set and base point (configuration)
• The integration test that supplies a key from the directory (test suite)

The test you can run

Ask a verifier where each input came from. If the answer for the key is "the library figures it out", the retrieval step is not evidenced.

Common failures

• The parameter set is assumed from the message rather than pinned by configuration.
• The key is taken from the message without a trust anchor.

How to close it

Write the input list before writing the verification code. It is short, it names the trust anchor for the key, and it is the first thing a reviewer needs in order to reason about the clause that follows. The artefact that opens the work is the verifier input list, one row per item with its source and bound; the row is only closed when that artefact is dated and has a person against it.

Where it sits against the base standard

The base standard does not carry this text. The amendment adds it, so an estate working from the 2018 edition alone will not find it. The citation has to name the amendment, and the record for 6.13.5.1 is the only place a reader can see it.