class TestClass { }
$TestObj=new TestClass();
$TestObj_assigned=$TestObj;
$TestObj_Refrenced=&$TestObj;
$TestObj_cloned=clone $TestObj;
$obj=new ReflectionClass('TestClass');
var_dump($obj->isInstance($TestObj));
var_dump($obj->isInstance($TestObj_assigned));
var_dump($obj->isInstance($TestObj_Refrenced));
var_dump($obj->isInstance($TestObj_cloned));