When the radius is only half the story: How G 1/24 is shaping claim interpretation at the EPO

Since the Enlarged Board of Appeal reached its conclusions in G 1/24, its decision has been fundamental to the interpretation of claims at the European Patent Office (EPO).  

Under the instruction that the description and drawings must always be consulted when interpreting the claims, the Boards of Appeal have been interpreting patent claims during opposition in a generally patentee-unfriendly manner.

A difficult landscape for patent owners #

Does the description of your patent contain some wording that implies your otherwise clear claims are narrower than might first appear, and this narrower interpretation will help you defend your patent in opposition?  Well, you’re out of luck; the claims are clear and should be interpreted broadly (T 2027/23).

Does the description of your patent contain some wording that implies your otherwise clear claims are broader than might first appear, and you really need to keep the narrow interpretation to defend your patent in opposition?  Well, you’re out of luck again, as the claim ‘must be construed in a broad manner’ (T 1849/23).

When the description saves the claim #

But all is not lost for the patentee!  In T 1620/23, the Board of Appeal set aside the decision of the Opposition Division and maintained the patent as granted after reinterpreting the claims in view of the description as instructed by G1/24.

The central issue in this case was the interpretation of a feature within claim 1 of the patent, which defined a specific ratio involving the "diameter (D)" of the wheel hub.  The problem for the patent owner was that a literal interpretation of the word "diameter" made the claim technically nonsensical.  As noted by the Board of Appeal, a primary recess located at a distance of 0.6 times the actual diameter from the centre would lie completely outside the physical wheel hub.

Making technical sense of the claim #

Following G 1/24, the Board of Appeal looked to the description and drawings to understand the skilled person's interpretation of the claim.  It found that in the patent's figures, the reference letter "D" was consistently used to indicate the radius of the wheel hub.

Therefore, the Board of Appeal concluded that a skilled person, faced with a literal interpretation that leads to a technical absurdity, would consult the description and figures and understand that "diameter" was intended to mean "radius" to give the claim technical sense. This interpretation was crucial to the patent's survival, rendering the previously nonsensical claim comprehensible and, in the Board of Appeal's view, patentable over the prior art.

Therefore, while G1/24 may make arguing for a narrow claim scope during opposition proceedings more challenging, that, like the diameter of T 1620/23, would only be half the story.

In a post-G 1/24 landscape, the relationship between claims and description is more important than ever. If you would like to review your drafting or opposition strategy in light of these developments, the team at Murgitroyd would be happy to assist.