6.2 Determination of filing date in cases of erroneously filed elements or parts of the international application

Rule 20.5bis PCT, which entered into force on 1 July 2020, allows applicants to correct an erroneously filed element (description or claims) or part of the description, claims or drawings (including all drawings) contained in an international application in the proceedings before the receiving Office. In particular, it allows this correction to be made by incorporating the correct element or part by reference to a priority application, on condition that it is completely contained in that priority application, which must have been validly claimed on the date of filing. Rule 56a, which governs erroneously filed application documents, entered into force on 1 November 2022, and the notification of incompatibility of Rule 20.5bis PCT with the EPC legal framework filed by the EPO under Rule 20.8(b-bis) PCT was withdrawn with effect from then. This means that requests for incorporation by reference that were granted by the receiving Office under Rule 20.5bis(d) PCT will have effect for Euro-PCT applications filed on or after 1 November 2022.

In these cases, the initially accorded international filing date is maintained, and the international application as filed therefore contains both the erroneously filed application documents and the correct application documents in the proceedings before the EPO as designated/elected Office. See also OJ EPO 2022, A71 and A‑XIII, 3.1 and 3.2 for details of the requirements as to the translation under Rule 159(1)(a). On the requirements as regards the payment of the additional fee as part of the filing fee under Rule 159(1)(c), see the April 2025 edition of the Guidelines, A‑III, 13.2.

For international applications filed between 1 July 2020 and 31 October 2022, the limitation under the procedure described in C‑III, 1.3 remains unchanged (see also the April 2025 edition of the Guidelines, A‑III, 13.2). This means that, if the receiving Office considered the correct application documents to be incorporated by reference under Rule 20.5bis(d) PCT, i.e. without changing the filing date, this incorporation will not have any effect in the proceedings before the EPO as designated/elected Office. For the general procedure for establishing the filing date and the application documents forming the basis of the proceedings, see A‑XIII, 3.1, 3.2 and C‑III, 1.3.