Welcome to the new version of the Patents Manual. Please note there are changes to the numbering and sequence of the chapters and pages in the manual. You are encouraged to take the time to explore and familiarise yourself with this new structure.

8.12.2 Balance of Probabilities

Date Published

Also in this Chapter:

The objections of novelty, inventive step and innovative step are raised, and maintained, on the balance of probabilities.

The balance of probabilities requires examiners to weigh up all the material before them and decide, on balance, whether an objection is more likely than not to be applicable. Another way of viewing the balance of probabilities is that the objection is highly plausiblemore probable than not or prima facie reasonable.

At first report, examiners need only determine whether an objection is prima facie reasonable. In response to the objection, applicants can provide submissions or evidence that shifts the balance of probabilities in their favour.  It is not sufficient for the applicant to merely raise doubts in the examiner’s mind; there must be a substantial doubt before an objection is withdrawn. In most cases, persuasive reasoned argument from the applicant in response would be sufficient to tip the scales in the applicant’s favour, however there may be circumstances where supporting evidence is required.  For example, if a statement in the submission is improbable, substantial supporting evidence would be required to convince an examiner. Supporting evidence would not be necessary where the submission is inherently probable.

Where doubt (even substantial doubt) is raised by the applicant, examiners need to consider whether the balance could be shifted in favour of maintaining the objection by identifying further information that would support the objection.  For example, evidence might be obtained that rebuts an assertion made by the applicant.

Submissions from applicants that a novelty or inventive/innovative step objection based on a foreign language document cannot be maintained, on the grounds that it has not been demonstrated that an English translation of the document (machine or otherwise) was available to the public before the priority date, should not be accepted.  In this situation, it is reasonable for examiners to argue that applying the balance of probabilities, the onus falls on the applicant to demonstrate that the relevant features are not disclosed in the document.

Balance of Probabilities - Questions of Law

The balance of probabilities only applies to questions of fact.  Thus, during examination, examiners should apply the balance of probabilities test in weighing up factual matters that form the basis for an objection.  Factual matters are most relevant in the context of novelty and inventive step.  For example, what a document would disclose to a skilled person, or what would be a matter of routine for the skilled addressee, should be determined on the balance of probabilities.  Having determined the facts, the relevant law can then be applied.

Questions of law, such as the proper construction of a claim, and whether a claim when properly construed defines a manner of manufacture, or novel or inventive subject matter, are not open to a balancing of probabilities or questions of doubt.  Consequently, submissions along those lines should not be accepted.  Any uncertainties in how the law is to be applied to the facts are to be resolved by the decision maker; during examination this is the examiner.

Amended Reasons

Amended Reason Date Amended
Back to top