Decision-time evidence
Mergetic is designed to preserve the proposed action, evaluation, disposition and responsible authority for each governed decision.
RESOURCE · PRA SS1/23
Support independent challenge.
Do not replace it.
SS1/23 first took effect on 17 May 2024. A clarifying amendment took effect on 23 April 2026; it did not replace the original framework. The statement sets model-risk-management expectations for specified UK banks, building societies and PRA-designated investment firms with internal model approval. Its five principles include governance and independent validation, and it identifies AI and machine-learning model risk within broader model risk.
Separate authority
Evaluation and routing are structurally separate from the governance authority that can prevent release at the agreed boundary.
Repeatable review
Illustrative records demonstrate a replayable, SHA-256-linked integrity chain that can support accountable review and independent challenge.
The boundary matters
These capabilities may support a firm's evidence framework. They do not replace independent model validation, establish compliance or determine whether SS1/23 applies.
NEXT STEP
Inspect the evidence, then validate the fit.
Use the official supervisory statement and amendment for the rule. Use the Mergetic Demo to inspect the decision record.