In order to overcome the language barrier constituted by a document in an unfamiliar non-official language, it might be appropriate for the examiner to rely on a machine translation of said document (see T 991/01), which should be is sent to the applicant (see B‑X, 9.1.3). If only part of the translated document is relevant, the particular passage relied upon must should be identified (see B‑XI, 3.2). A translation has to serve the purpose of rendering the meaning of the text in a familiar language (see B‑X, 9.1.3). Therefore mere grammatical or syntactical errors which have no impact on the possibility of understanding the content do not hinder its qualification as a translation (see T 287/98).
A general statement that machine translations as such cannot be trusted is not sufficient to invalidate the probatory value of the translation. If a party objects to the use of a specific machine translation, that party bears the burden of adducing evidence (in the form of, for instance, an improved translation of the whole or salient parts of the document) showing the extent to which the quality of the machine translation is defective and should therefore not be relied upon.
When the party provides substantiated reasoning for questioning the objections raised based on the translated text, the examiner must will have to take these reasons into account, similarly to when the publication date is questioned (see G‑IV, 7.5.3).