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Non-Patent Literature reference numbers (XP)

NPL reference numbers are numbers assigned to non-patent literature (XP) documents.


In Espacenet, only XP documents which have been classified and/or cited in the search report produced at the EPO are available.


The XP number format is: XP followed by a serial number (variable, maximum nine digits).


Examples: XP1, XP000123456.


It is not possible either to retrieve an XP document with the name of the author or to limit a search to XP documents only.


XP documents can be retrieved by entering the corresponding number in the Smart search mask.


For more information on Espacenet, see the following pages: