Annex IV of the EU AI Act lists the technical documentation a provider of a high-risk AI system must be able to produce. Buried in that list is a set of expectations about your data that trip up more teams than the model documentation does. This is a plain-English read of what Annex IV actually asks for, and why.
The four things Annex IV wants about your data
In substance, four things. First, provenance: where your training, validation and testing data came from. Second, methodology: how it was collected, labelled and prepared. Third, quality and bias measures: what you did to check representativeness and detect errors and bias. Fourth, human oversight: how humans were involved and how their judgment was applied.
Notice the shape of the ask. It is not 'is your data good?' It is 'can you show how your data was produced and checked?' That is a documentation and traceability requirement, not a quality score.
How it connects to Article 10
Annex IV does not stand alone. Article 10 sets out the data governance obligations (relevance, representativeness, examination for bias and gaps), and Annex IV is where you evidence that you met them. Read together, they describe a loop: govern the data well, and document that you did, in a form an auditor can follow.
The traceability principle underneath it
The through-line is traceability: for any output in your dataset, can you show who produced it, under what instructions, and who reviewed it? Teams that can answer that from a record sail through; teams that cannot end up reconstructing history under deadline, which is exactly the evidence regulators trust least.
Common misconceptions
Two myths cause most pain. The first is that Annex IV is a one-time document you write before launch; in reality it should reflect a living record captured as work happens. The second is that a polished narrative is enough; auditors want to trace specific examples, not read a summary. Build for the trace, not the summary.
Turn the requirement into a workflow
The efficient path is to make provenance a by-product of how data is produced, so your Annex IV documentation assembles itself. Pathwize records provenance at every step and maps it to Annex IV fields. Book a demo to see it with your compliance and ML teams.