It is general practice to supplement a patent application with information from a cross-referenced document, although the conditions are very limited under the EPC. Recently, the Boards of Appeal of the EPO has to decide on a case which contains a reference to a U.S. Patent Application Serial No. (Attorney Docket No.) filed concurrently herewith, the disclosure of which is hereby incorporated by reference (T 1436/12). Even though, U.S. patent applications can be searched and retrieved by their docket number, at the filing date of a European patent application the referenced U.S. patent application cannot have been available to the public from the USPTO via its docket number or otherwise. Consequently, the docket number could not be replaced by a filing or publication number, and the cross-referenced document could not supplement an otherwise incomplete disclosure of a patent application.
The take home message from this case is to incorporate the information from another document directly and unambiguously into the original patent application prior to filing the application with the patent office, instead of referring only to a filing, publication or even docket number.