Chapter IV – Prior art
It should be noted that for the purpose of international preliminary examination all prior art is taken into account which was publicly available before the international filing date or, where a priority has been validly claimed, before the date of priority. It should be remembered that different claims, or different alternatives claimed in one claim, may have different effective dates, i.e. the date of filing or (one of) the claimed priority date(s). The question of novelty must be considered against each claim (or part of a claim where a claim specifies a number of alternatives), and prior art in relation to one claim or one part of a claim may include matter, e.g. an intermediate document (see GL/PCT‑EPO B‑X, 9.2.4), which cannot be cited against another claim or another alternative in the same claim because it has an earlier effective date.
If the applicant subsequently furnishes missing parts of the description, parts of the claims or all or parts of the drawings under Rule 20.5, the international filing date is the date on which the purported international application is completed by the furnishing of the missing parts, unless the missing parts are completely contained in the priority document and the requirements given in Rule 20.6 are satisfied, in which case the original filing date is maintained. The date of the application as a whole is thus either the date on which the missing parts are received or the original filing date (see GL/PCT‑EPO C‑III, 2, and GL/PCT‑EPO H‑II, 2.2.2).
If the applicant subsequently furnishes (a) correct element(s) (an element being the description or the claims) or correct parts of the description, parts of the claims or all or parts of the drawings under Rule 20.5bis, the international filing date is the date on which the purported international application is corrected by the furnishing of the correct elements or parts, unless the correct elements or parts are completely contained in the priority document and the requirements given in Rule 20.6 are satisfied, in which case the original filing date is maintained. The date of the application as a whole is thus either the date on which the correct elements or parts are received or the original filing date (see GL/PCT‑EPO C‑III, 2, and GL/PCT‑EPO H‑II, 2.2.2).