Why Annex IV Is the Heart of Compliance
For a high-risk AI system, Annex IV technical documentation is the compliance evidence. The conformity assessment examines it, the regulator requests it, and the EU declaration of conformity rests on it. If your documentation is thin, your compliance is thin — no amount of good engineering rescues a missing technical file. The good news is that Annex IV is a defined list, so you always know what “done” looks like.
The Nine Content Areas of Annex IV
1. General description of the system. Its intended purpose, the provider, versions, how it interacts with hardware or other software, the forms in which it is placed on the market, and the hardware it runs on. This is the orientation section a regulator reads first.
2. Detailed description of the elements and development process. The methods and steps used to develop the system, design choices and rationale, system architecture, computational resources, data requirements, human-oversight measures, and pre-determined changes. This is the largest and most technical section.
3. Monitoring, functioning and control. The system's capabilities and limitations, expected accuracy for specific persons or groups, foreseeable unintended outcomes and risks to health, safety, and fundamental rights, and the human-oversight measures and technical measures that mitigate them.
4. Performance metrics. A description of the appropriateness of the performance metrics used, and the system's accuracy, robustness, and cybersecurity.
5. Risk management system. A detailed description of the Article 9 risk management system — how risks are identified, evaluated, and mitigated across the lifecycle.
6. Lifecycle changes. A description of relevant changes made through the system's lifecycle, so that the documentation stays a living record rather than a launch snapshot.
7. Standards applied. A list of the harmonised standards applied in full or in part, and where they were not applied, a description of the solutions adopted to meet the requirements.
8. EU declaration of conformity. A copy of the signed declaration of conformity for the system.
9. Post-market monitoring plan. A detailed description of the system in place to evaluate the system's performance in the post-market phase, in line with Article 72.
A Practical Build Order
Annex IV is listed as a content specification, but you do not have to write it in that order. The most efficient sequence starts with the general description (section 1), because it forces clarity on intended purpose — which drives everything downstream. Then build the risk management system (section 5) and the development description (section 2) in parallel, since they share inputs. Performance metrics and the monitoring/control narrative (sections 3 and 4) follow naturally from testing. Standards (section 7), the declaration (section 8), and the post-market plan (section 9) come last, once the substance is settled. Treat lifecycle changes (section 6) as an ongoing log from day one.
Common Mistakes to Avoid
The two failures regulators see most are snapshot documentation — a file written at launch and never updated, which breaks section 6 immediately — and narrative without evidence, where the file asserts the system is accurate and robust but contains no test results, datasets descriptions, or metrics to back it up. Annex IV rewards traceability: every claim should point to an artefact. The third common gap is forgetting the post-market monitoring plan, which is genuinely required content, not an optional extra.
Make It Easier
GeraCompliance provides an Annex IV technical documentation template structured around these nine sections, so you fill in evidence rather than design a document from scratch. Pair it with the conformity assessment guide and the compliance checklist to keep the whole high-risk programme on track. For a deadline build, the AI Act sprint assembles an assessment-ready Annex IV file in days.