4. The computer implemented method of claim 1 , wherein annotating a portion of the first document corresponding to the obsolete data with the data from the second document to form an annotated first document further comprises: responsive to serving the first document to the user, injecting markup into the first document to annotate the portion of the first document.
5. The computer implemented method of claim 4 , wherein the markup is injected into the first document to annotate the obsolete data in the portion of the first document without modifying remaining portions of the first document.