7.5.2 Standard of proof 

When an internet document is cited against an application or patent, the same facts are to be established as for any other piece of evidence, including standard paper publications (see G‑IV, 1). This evaluation is made in accordance with the principle of "free evaluation of evidence" (see T 482/89 and T 750/94). That means that each piece of evidence is weighted according to its probative value, which is evaluated in view of the particular circumstances of each case. The standard for assessing these circumstances is the balance of probabilities. According to this standard, it is not sufficient that the alleged fact (e.g. the publication date) is merely probable; the examining division must be convinced that it is correct. It does mean, however, that proof beyond reasonable doubt ("up to the hilt") of the alleged fact is not required.

The publication dates of internet disclosures submitted by a party to opposition proceedings are assessed on the basis of the same principles as are applied in examination proceedings, i.e. they are assessed in view of the specific circumstances of the case. In particular, the timing of the submission and the interests of the party submitting the disclosure are to be taken into account.

Internet disclosures often contain an explicit publication date. This date is generally considered reliable and accepted at face value. The applicant bears the burden of proving otherwise. Circumstantial evidence may be required to establish or confirm the publication date (see G‑IV, 7.5.4). If the examiner concludes that – on the balance of probabilities – it has been established that a particular document was available to the public on a particular date, this date is taken as the publication date for the purposes of examination.