Generally, where the search is concluded less than eighteen months after the European or international filing date of the application (the filing date according to Art. 80 and not its claimed priority date(s)), it will not be possible at the time of the search to make a complete search for potentially conflicting European and international applications. This search therefore has to be completed at the examination stage by the examining division (see C‑IV, 7.1). If the search division becomes aware of potentially conflicting published documents, these documents are cited in the search report.
Patent documents, regardless of their state or region of origin, which have a filing or valid priority date prior to the filing date of the application being searched (not the priority date), but which are published on or after the filing date of the application being searched and contain novelty-destroying subject-matter for at least one independent claim of the application, are referred to as "E" documents, see B‑X, 9.2.6.
"E" documents cited in an EP search report can be other EP or WO applications with an earlier priority date (Art. 54(3)) which are relevant because they anticipate the novelty of the subject-matter claimed in the application being searched.
In this regard it must be stressed that the "E" document is novelty-destroying prior art under Art. 54(3) if it discloses the subject-matter in question in any of its parts (i.e. claims, description or drawings).