diff --git a/mockserver-core/src/main/java/org/mockserver/collections/ImmutableEntry.java b/mockserver-core/src/main/java/org/mockserver/collections/ImmutableEntry.java
index d483cf10b..1f186080b 100644
--- a/mockserver-core/src/main/java/org/mockserver/collections/ImmutableEntry.java
+++ b/mockserver-core/src/main/java/org/mockserver/collections/ImmutableEntry.java
@@ -45,6 +45,10 @@ public boolean isNotOptional() {
         return !isOptional();
     }
 
+    public boolean isNotNotted() {
+        return !isNotted();
+    }
+
     @Override
     public NottableString getLeft() {
         return key;
diff --git a/mockserver-core/src/main/java/org/mockserver/collections/SubSetMatcher.java b/mockserver-core/src/main/java/org/mockserver/collections/SubSetMatcher.java
index 2eaf2eb5d..e6e36375a 100644
--- a/mockserver-core/src/main/java/org/mockserver/collections/SubSetMatcher.java
+++ b/mockserver-core/src/main/java/org/mockserver/collections/SubSetMatcher.java
@@ -28,9 +28,12 @@ static boolean containsSubset(MockServerLogger mockServerLogger, MatchDifference
         }
 
         if (result) {
-            long subsetNonOptionalSize = subset.stream().filter(ImmutableEntry::isNotOptional).count();
+            long subsetRequiredSize = subset.stream()
+                .filter(ImmutableEntry::isNotOptional)
+                .filter(ImmutableEntry::isNotNotted)
+                .count();
             // this prevents multiple items in the subset from being matched by a single item in the superset
-            result = matchingIndexes.size() >= subsetNonOptionalSize;
+            result = matchingIndexes.size() >= subsetRequiredSize;
         }
         return result;
     }