Also called: unreported change, silent change
In plain words
Most verification checks whether what an agent said it did really happened. The more dangerous case is the reverse: something happened that the agent didn't mention. A budget raised with no report, a bid changed, a campaign paused. Plain logging can't catch it, because an agent that didn't mention a change didn't log it either.
How QED Proof uses it
This is part of pipelines, which are designed and accepted but not live yet. In a pipeline's watch mode, QED Proof reads the destination's own change history on a schedule: the Meta ad account's activity log, or Google Ads' change_event records. It matches each change against open claims. A change inside the pipeline's filter that no claim explains is an unclaimed change.
The decision recorded in ADR-010 is that each unclaimed change becomes a signed, logged observation entry: the same log and the same signature as a receipt, but with no claim, plus an alert. That needs a minor version of the receipt spec, with test vectors first, as with every spec change.
Example
A marketer's pipeline watches campaigns A and B for budget changes of $50 or more. The agent reports raising A's budget, and that's verified. The activity log also shows B's budget changed by the same app, with no claim. That second change is an unclaimed change, and it triggers an alert.