diff --git a/onchain/src/Optimizer.sol b/onchain/src/Optimizer.sol
index 08b8769..1fd2e82 100644
--- a/onchain/src/Optimizer.sol
+++ b/onchain/src/Optimizer.sol
@@ -361,11 +361,13 @@ contract Optimizer is Initializable, UUPSUpgradeable, IOptimizer {
         virtual
         returns (uint256 capitalInefficiency, uint256 anchorShare, uint24 anchorWidth, uint256 discoveryDepth)
     {
-        // Guard against non-zero shift and negative mantissa.
+        // Guard against non-zero shift, negative mantissa, and overflow.
+        // All 8 slots must be in [0, 1e18] — the uniform dyadic range.
         // shift is reserved for future use; uint256() cast silently wraps negatives.
         for (uint256 k; k < 8; k++) {
             require(inputs[k].shift == 0, "shift not yet supported");
             require(inputs[k].mantissa >= 0, "negative mantissa");
+            require(inputs[k].mantissa <= 1e18, "mantissa overflow");
         }
         // Extract slots 0 and 1 (shift=0 enforced above — mantissa IS the value)
         uint256 percentageStaked = uint256(inputs[0].mantissa);
diff --git a/onchain/src/OptimizerV3Push3Lib.sol b/onchain/src/OptimizerV3Push3Lib.sol
index da3774b..0a7f870 100644
--- a/onchain/src/OptimizerV3Push3Lib.sol
+++ b/onchain/src/OptimizerV3Push3Lib.sol
@@ -17,14 +17,13 @@ library OptimizerV3Push3Lib {
         pure
         returns (uint256 ci, uint256 anchorShare, uint24 anchorWidth, uint256 discoveryDepth)
     {
-        // Validate mantissa for percentageStaked
-        require(inputs[0].mantissa <= 1e18, "mantissa overflow");
-
-        // Validate that shift is 0 (future-only field, not yet supported)
-        // and that no mantissa is negative (uint256 cast silently wraps negatives).
+        // Validate that shift is 0 (future-only field, not yet supported),
+        // that no mantissa is negative (uint256 cast silently wraps negatives),
+        // and that all slots are within the [0, 1e18] dyadic range.
         for (uint256 k = 0; k < 8; k++) {
             require(inputs[k].shift == 0, "shift not yet supported");
             require(inputs[k].mantissa >= 0, "negative mantissa");
+            require(inputs[k].mantissa <= 1e18, "mantissa overflow");
         }
 
         uint256 percentagestaked = uint256(uint256(inputs[0].mantissa));