Art. 153(5) EPC states that a Euro-PCT application shall be considered as comprised in the state of the art under Art. 54(3) EPC if the conditions laid down in Art. 153(3) or (4) EPC "and in the Implementing Regulations" are fulfilled.

Pursuant to R. 165 EPC a Euro‑PCT application shall be considered as comprised in the state of the art under Art. 54(3) EPC if in addition to the conditions laid down in Art. 153(3) or (4) EPC (publication of the international application or its translation), the filing fee under R. 159(1)(c) EPC has been paid. Thus once the filing fee is paid for the conflicting application, it is considered to be an Art. 54(3) EPC application.

Under former Art. 158(2) EPC 1973, a Euro-PCT application was considered to be an Art. 54(3) EPC application if a translation was filed (where necessary) and the national fee paid.

In T 404/93 the European patent application was limited to the contracting states Italy (IT), Netherlands (NL) and Sweden (SE) in view of an earlier international application, published after the filing date of the former. The board noted that the earlier PCT application had mentioned several EPC contracting states, including IT, NL and SE, as being designated for a European patent. However, when the earlier application had entered the European phase, no designation fees had been paid for IT, NL and SE. Accordingly, the board found that the earlier international application was not comprised in the state of the art under Art. 54(3) EPC 1973 for IT, NL and SE (see also T 623/93).

In T 622/91 the respondent (patent proprietor) requested that the decision under appeal be set aside and the patent maintained for all designated contracting states. Two earlier international applications and the European patent had designated the contracting state France (FR). The board noted that the requirements of Art. 158(2) EPC 1973 (now Art. 153(3) and (4) EPC and R. 159 EPC) were fulfilled, and considered the international applications as comprised in the state of the art relevant to the patent in suit in accordance with Art. 54(3) and Art. 158(1) EPC 1973 (now Art. 153(5) EPC). The board went on to examine claim 1 of the main request and found that the earlier application was novelty-destroying in so far as the same contracting state FR was designated.

In T 1010/07 the board held that E4, a document cited in relation to inventive step which had been published before the priority date of the contested patent, was a publication under Art. 158(3) EPC 1973, i.e. the publication of a translation supplied to the EPO under Art. 158(2) EPC 1973 into an EPO official language (English) of an international application not published in an official language (Japanese). Although translations under Art. 158(2) EPC 1973 were not checked by the EPO, it was presumed that their content was identical to that of the published international application (see e.g. T 605/93). Only when there were reasonable grounds to doubt this presumption in a particular case was further investigation and, where necessary, the production of evidence required. Thus, as a translation of identical content, E4 was to be regarded as forming part of the prior art.