diff --git a/src/Tokenizers/PHP.php b/src/Tokenizers/PHP.php
index 3d8cee1657..8d2e3779d2 100644
--- a/src/Tokenizers/PHP.php
+++ b/src/Tokenizers/PHP.php
@@ -2583,6 +2583,7 @@ protected function processAdditional()
                     T_STATIC       => T_STATIC,
                     T_FALSE        => T_FALSE,
                     T_NULL         => T_NULL,
+                    T_NAMESPACE    => T_NAMESPACE,
                     T_NS_SEPARATOR => T_NS_SEPARATOR,
                 ];
 
diff --git a/tests/Core/Tokenizer/BitwiseOrTest.inc b/tests/Core/Tokenizer/BitwiseOrTest.inc
index ec1801d569..2af0ecae98 100644
--- a/tests/Core/Tokenizer/BitwiseOrTest.inc
+++ b/tests/Core/Tokenizer/BitwiseOrTest.inc
@@ -24,6 +24,15 @@ class TypeUnion
         /* testTypeUnionPropertyMulti3 */
         | null $arrayOrFalse;
 
+    /* testTypeUnionPropertyNamespaceRelative */
+    public namespace\Sub\NameA|namespace\Sub\NameB $namespaceRelative;
+
+    /* testTypeUnionPropertyPartiallyQualified */
+    public Partially\Qualified\NameA|Partially\Qualified\NameB $partiallyQual;
+
+    /* testTypeUnionPropertyFullyQualified */
+    public \Fully\Qualified\NameA|\Fully\Qualified\NameB $fullyQual;
+
     public function paramTypes(
         /* testTypeUnionParam1 */
         int|float $paramA /* testBitwiseOrParamDefaultValue */ = CONSTANT_A | CONSTANT_B,
@@ -35,6 +44,15 @@ class TypeUnion
         return (($a1 ^ $b1) |($a2 ^ $b2)) + $c;
     }
 
+    public function identifierNames(
+        /* testTypeUnionParamNamespaceRelative */
+        namespace\Sub\NameA|namespace\Sub\NameB $paramA,
+        /* testTypeUnionParamPartiallyQualified */
+        Partially\Qualified\NameA|Partially\Qualified\NameB $paramB,
+        /* testTypeUnionParamFullyQualified */
+        \Fully\Qualified\NameA|\Fully\Qualified\NameB $paramC,
+    ) {}
+
     /* testTypeUnionReturnType */
     public function returnType() : int|false {}
 
@@ -43,6 +61,15 @@ class TypeUnion
 
     /* testTypeUnionAbstractMethodReturnType1 */
     abstract public function abstractMethod(): object|array /* testTypeUnionAbstractMethodReturnType2 */ |false;
+
+    /* testTypeUnionReturnTypeNamespaceRelative */
+    public function identifierNamesReturnRelative() : namespace\Sub\NameA|namespace\Sub\NameB {}
+
+    /* testTypeUnionReturnPartiallyQualified */
+    public function identifierNamesReturnPQ() : Partially\Qualified\NameA|Partially\Qualified\NameB {}
+
+    /* testTypeUnionReturnFullyQualified */
+    public function identifierNamesReturnFQ() : \Fully\Qualified\NameA|\Fully\Qualified\NameB {}
 }
 
 /* testTypeUnionClosureParamIllegalNullable */
diff --git a/tests/Core/Tokenizer/BitwiseOrTest.php b/tests/Core/Tokenizer/BitwiseOrTest.php
index f6288d817e..d4a27bdc33 100644
--- a/tests/Core/Tokenizer/BitwiseOrTest.php
+++ b/tests/Core/Tokenizer/BitwiseOrTest.php
@@ -102,13 +102,22 @@ public function dataTypeUnion()
             ['/* testTypeUnionPropertyMulti1 */'],
             ['/* testTypeUnionPropertyMulti2 */'],
             ['/* testTypeUnionPropertyMulti3 */'],
+            ['/* testTypeUnionPropertyNamespaceRelative */'],
+            ['/* testTypeUnionPropertyPartiallyQualified */'],
+            ['/* testTypeUnionPropertyFullyQualified */'],
             ['/* testTypeUnionParam1 */'],
             ['/* testTypeUnionParam2 */'],
             ['/* testTypeUnionParam3 */'],
+            ['/* testTypeUnionParamNamespaceRelative */'],
+            ['/* testTypeUnionParamPartiallyQualified */'],
+            ['/* testTypeUnionParamFullyQualified */'],
             ['/* testTypeUnionReturnType */'],
             ['/* testTypeUnionConstructorPropertyPromotion */'],
             ['/* testTypeUnionAbstractMethodReturnType1 */'],
             ['/* testTypeUnionAbstractMethodReturnType2 */'],
+            ['/* testTypeUnionReturnTypeNamespaceRelative */'],
+            ['/* testTypeUnionReturnPartiallyQualified */'],
+            ['/* testTypeUnionReturnFullyQualified */'],
             ['/* testTypeUnionClosureParamIllegalNullable */'],
             ['/* testTypeUnionWithReference */'],
             ['/* testTypeUnionWithSpreadOperator */'],