An invention is "considered to be new if it does not form part of the state of the art". The "state of the art" is defined as "everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of the European patent application". The width of this definition is to be noted. There are no restrictions whatever as to the geographical location where or the language or manner in which the relevant information was made available to the public; also no age limit is stipulated for the documents or other sources of the information. There are, however, certain specific exclusions (see G‑V). However, since the "state of the art" available to the examiner will mainly consist of the documents listed in the search report, G‑IV, 3 to 6, deals with the question of public availability only in relation to written description (either alone or in combination with an earlier oral description or use).
The principles to be applied in determining whether other kinds of prior art (which could be introduced into the proceedings e.g. by a third party under Art. 115) have been made available to the public are set out in G‑IV, 7.1 to G-IV, 7.4.
A written description, i.e. a document, is regarded as made available to the public if, at the relevant date, it was possible for members of the public to gain knowledge of the content of the document and there was no bar of confidentiality restricting the use or dissemination of such knowledge. For instance, German utility models ("Gebrauchsmuster") are already publicly available as of their date of entry in the Register of utility models ("Eintragungstag"), which precedes the date of announcement in the Patent Bulletin ("Bekanntmachung im Patentblatt"). The search report also cites documents in which doubts with regard to the fact of public availability (for "in-house state of the art", see F‑II, 4.3) and doubts concerning the precise date of publication (see B‑VI, 5.6, and G‑IV, 7.5) of a document have not, or not fully, been removed (see B‑VI, 5.6, and G‑IV, 7.5).
If the applicant contests the public availability or assumed date of publication of the cited document, the examiner needs to consider whether to investigate the matter further. If the applicant shows sound reasons for doubting whether the document forms part of the "state of the art" in relation to his the application and any further investigation does not produce evidence sufficient to remove that doubt, the examiner does not pursue the matter further. The only other problem likely to arise for the examiner is where:
In such cases, the examiner starts with the assumption that the document gives a true account of the earlier lecture, display or other event and therefore regards the earlier event as forming part of the "state of the art". If, however, the applicant gives sound reasons for contesting the truth of the account given in the document then again the examiner does not pursue the matter further.