Article 4(3) provides that for claims involving non-high-risk AI systems the 4(1) causal-link presumption applies only where the national court considers it excessively difficult for the claimant to prove the causal link. The aim is to avoid extending the presumption broadly to all AI systems while still ensuring that opacity does not block recovery in genuinely intractable cases.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.