Lowering the bar for novelty of sub-ranges
15 May 2025
The test for novelty at the European Patent Office (EPO) is centred around the so called “gold standard” whereby a prior art disclosure anticipates a claim if it directly and unambiguously discloses all of the claimed features in combination.
However, over the years, a requirement has developed from the case law for evaluating whether a claimed sub-range is novel over a prior art disclosure. According to the criteria, for a sub-range to be novel it must be:
- Narrower compared with the known range; and
- Sufficiently far removed from any specific examples disclosed in the prior art and from the endpoints of the known range.
As reported in our previous article, there used to be a third “purposive selection” requirement within this test, which was removed from the EPO Guidelines for Examination in 2019 as it was considered only to be relevant in the assessment of inventive step.
However, recent decisions from the Boards of Appeal (BoA) have raised questions about the remaining criteria, in its entirety.
In the recent decision T 667/23, the BoA concluded that the two-step test for novelty of sub-ranges could not be reconciled with the EPO’s gold standard of direct and unambiguous disclosure.
The case at hand related to an aluminium alloy composition which consisted of, inter alia, 1.03 – 1.40 wt.% Si. The prior art disclosed an alloy falling within the scope of claim 1, except that it contained 1.00 wt.% Si. The opponents argued that the lower endpoint of the claimed range (1.03 wt.%) could not establish novelty since it was not sufficiently far removed from the example.
The Board disagreed, referencing previous decision T 1688/20 (Reasons 3.2.1.), stating that the concept of “narrower” and “sufficiently far removed” do not provide an objective, solid and consistent criteria for establishing the novelty of a selected sub-range. The Board considered that such criteria instead was relevant for inventive step.
The Board also suggested that the criterion of “serious contemplation” which is applied to the assessment of novelty of selection inventions involving multiple, overlapping ranges was also relevant to inventive step, and not novelty.
This would suggest that the bar for acquiring novelty of a claimed sub-range is being lowered at the EPO. However, time will tell whether such conclusions spread to other BoA and/or become adopted in the EPO’s Guidelines for Examination. Such a change in the law would have ramifications in various technology sectors, where patent applications often feature range(s), such as pharmaceuticals, consumer products and alloys.
Additionally, such criteria would almost certainly not vanish completely in the assessment of patentability of sub-ranges, and would instead be raised in the subsequent inventive step assessment.
Bradley Wilson
Life Sciences & Chemistry group
This publication is a general summary of the law. It should not replace legal advice tailored to your specific circumstances.
© Withers & Rogers LLP May 2025
