diff --git a/contracts/vault/src/lib.rs b/contracts/vault/src/lib.rs
index 383b39e4..29618060 100644
--- a/contracts/vault/src/lib.rs
+++ b/contracts/vault/src/lib.rs
@@ -274,6 +274,8 @@ pub enum DataKeyExt {
     // Issue #1174: gate for the contract telemetry / debugging hook
     DiagnosticsEnabled,
 
+    // Issue #1173 / #1231: nested to stay within DataKeyExt variant limits
+    Risk(RiskExtKey),
     // Issue #1230: Performance fee switch for strategy performance incentives
     PerformanceFeeBps,
     PerformanceIncentivePool,
@@ -1375,12 +1377,22 @@ impl YieldVault {
                     let token = Self::token(env.clone());
                     let price_data = oracle_client.get_price(&token, &token);
                     let max_age = Self::oracle_heartbeat(env.clone());
+                    let last: Option<oracle::PriceData> = env
+                        .storage()
+                        .instance()
+                        .get(&DataKeyExt::Risk(RiskExtKey::LastPx));
                     let last_price = Self::last_oracle_price(&env);
                     oracle::OracleValidator::validate_price_data(
                         &env,
                         &price_data,
                         max_age,
                         Some(oracle::MAX_PRICE_DEVIATION_BPS),
+                        last.as_ref(),
+                    )
+                    .expect("OracleValidationFailed");
+                    env.storage()
+                        .instance()
+                        .set(&DataKeyExt::Risk(RiskExtKey::LastPx), &price_data);
                         last_price.as_ref(),
                     )
                     .map_err(|_| VaultError::OracleValidationFailed)?;