diff --git a/index.bs b/index.bs
index 328ff1b4..1a109ce9 100644
--- a/index.bs
+++ b/index.bs
@@ -3657,6 +3657,7 @@ partial interface MLGraphBuilder {
     1. If [=MLGraphBuilder/validating operand=] with [=this=] and any of |input|, |options|.{{MLLayerNormalizationOptions/scale}} (if it [=map/exists=]), and |options|.{{MLLayerNormalizationOptions/bias}} (if it [=map/exists=]) returns false, then [=exception/throw=] a {{TypeError}}.
     1. If |input|'s [=MLOperand/dataType=] is not {{MLOperandDataType/"float32"}} or {{MLOperandDataType/"float16"}}, then [=exception/throw=] a {{TypeError}}.
     1. If |options|.{{MLLayerNormalizationOptions/axes}} does not [=map/exist=], then set |options|.{{MLLayerNormalizationOptions/axes}} to a new [=/list=], either equal to [=the range=] from 1 to |input|'s [=MLOperand/rank=], exclusive, if |input|'s [=MLOperand/rank=] is greater than 1, or an empty [=/list=] otherwise.
+    1. Otherwise, if |options|.{{MLLayerNormalizationOptions/axes}} contains duplicate values, or if any of its elements is not in [=the range=] 0 to |input|'s [=MLOperand/rank=], exclusive, then return failure.
     1. If |options|.{{MLLayerNormalizationOptions/scale}} [=map/exists=]:
         1. If its [=MLOperand/dataType=] is not equal to |input|'s [=MLOperand/dataType=], then [=exception/throw=] a {{TypeError}}.
         1. If its [=MLOperand/rank=] is not equal to |options|.{{MLLayerNormalizationOptions/axes}}'s [=list/size=], then [=exception/throw=] a {{TypeError}}.