 <p>Your lists are sharing the same objects, if you modify the first element from arrReg you will see the modification also in arrRegOld - it is not related to binding. You need to clone the objects. You have several choices:</p> <p>a) Implement a clone method for your objects (recommended) b) Use a generic method like this one:</p> <pre><code> private function clone(source:Object):* { var array:ByteArray=new ByteArray(); array.writeObject(source); array.position=0; return(array.readObject()); } </code></pre> <p>and call arrRegOld = clone (arrReg); after arrReg = WSAutoreg.list.lastResult as ArrayCollection;</p>