diff --git a/src/Symfony/Component/Validator/Mapping/ClassMetadata.php b/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
index 2819ce1553ce2..d38dd322b3a4b 100644
--- a/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
+++ b/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
@@ -308,7 +308,6 @@ public function mergeConstraints(ClassMetadata $source)
                 $member = clone $member;
 
                 foreach ($member->getConstraints() as $constraint) {
-                    $member->constraintsByGroup[$this->getDefaultGroup()][] = $constraint;
                     $constraint->addImplicitGroupName($this->getDefaultGroup());
                 }
 
diff --git a/src/Symfony/Component/Validator/Tests/Mapping/ClassMetadataTest.php b/src/Symfony/Component/Validator/Tests/Mapping/ClassMetadataTest.php
index 34c62445a428b..f8feeda5bd380 100644
--- a/src/Symfony/Component/Validator/Tests/Mapping/ClassMetadataTest.php
+++ b/src/Symfony/Component/Validator/Tests/Mapping/ClassMetadataTest.php
@@ -153,26 +153,11 @@ public function testMergeConstraintsMergesMemberConstraints()
             $constraintA2,
         );
 
-        $constraintsByGroup = array(
-            'Default' => array(
-                $constraintA1,
-                $constraintA2,
-            ),
-            'EntityParent' => array(
-                $constraintA1,
-            ),
-            'Entity' => array(
-                $constraintA1,
-                $constraintA2,
-            ),
-        );
-
         $members = $this->metadata->getPropertyMetadata('firstName');
 
         $this->assertCount(1, $members);
         $this->assertEquals(self::PARENTCLASS, $members[0]->getClassName());
         $this->assertEquals($constraints, $members[0]->getConstraints());
-        $this->assertEquals($constraintsByGroup, $members[0]->constraintsByGroup);
     }
 
     public function testMemberMetadatas()