Documents cited in the application under consideration should be examined if they are cited as the starting point of the invention, as showing the state of the art, or as giving alternative solutions to the problem concerned, or when they are necessary for a correct understanding of the application (see, however, IV, 2.4). However, when such citations clearly relate only to details not directly relevant to the claimed invention, they may be disregarded. In the exceptional case that the application cites a document that is not published or otherwise not accessible to the Search Division and the document appears essential to a correct understanding of the invention to the extent that a meaningful search would not be possible without knowledge of the content of that document, the Search Division should postpone the search and request the applicant to provide first a copy of the document, if possible doing so within the time limit for the preparation of the search report. If no copy of the document is received within a time limit specified by the Search Division, a first attempt is made to carry out the search and then, if necessary, an incomplete search report or, where applicable, a declaration replacing the search report under Rule 63 is prepared. This incomplete search report or declaration will be issued giving the following grounds:

It should also be noted that where the applicant furnishes the document after the search report and the search opinion (if applicable, see XII, 8) have been prepared, an additional search on that subject-matter originally excluded from the search may be carried out due to the correction of the deficiency which led to the incomplete search (see C-VI, 8.2). However, applicants must be aware that such later furnished information can only be taken into account for sufficiency of disclosure pursuant to Art. 83 under certain circumstances (see C-II, 4.17).