Insufficient Optics - Sufficiency through the objective lens of the EPO (T0123/16)

Insufficient Optics - Sufficiency through the objective lens of the EPO (T0123/16)

It is not often that the world of optics produces contentious patents. It is even rarer for a patent in this field to be revoked on the basis of insufficient disclosure. And yet, this is what happened recently to an Olympus patent.


This recent Board of Appeal decision concerns an appeal by Olympus Corporation against the decision of the opposition division to revoke its patent for lack of novelty and inventive step. The opposition was lodged by another industry giant, Leica Microsystems. What makes this case interesting is that the appeal was dismissed, not on the original grounds of novelty and inventive step but based on insufficient disclosure in the description of how to make the invention actually work.

The invention

Olympus’s invention related to a microscope with an illuminating device whose key feature was the inclusion of “at least one lens configured to change the numerical aperture of the illumination light focused into a point on the pupil plane of the objective lens."

The Decision

The Board of Appeal concluded that the skilled person does not know how to influence the numerical aperture with at least one lens and the characteristics of the “at least one lens” are silent about how the desired function is achieved. Moreover, the board suggested that the patent as a whole is not clear how the said lens can be configured in order to change the numerical aperture in the claimed system and that the skilled person would not be enabled by the information provided in the patent to carry out the invention.
Sufficiency relates to the EPO’s requirement that the application as a whole (claims, description and drawings) provides enough detail to enable the skilled person in the art to carry out the invention – without undue burden or exercising inventive skill – based on their common general knowledge. Although it is not necessary to provide well-known ancillary features, the EPO requires that the description discloses the “essential features” of the invention in sufficient detail for the skilled person to be able to put the invention into practice. Here they basically questioned the underlying physics of the description – even a skilled reader would have to go away and do more inventing to put the key feature into effect.


There are perhaps two important takeaways from this decision: one legal and one technical. Legally speaking, once opposed, the opposition division and the board of appeal are not restricted to making decisions based on the opposition grounds raised by the opponent: they can look at other grounds, as was done in this case. 
From a technical point of view, when drafting an application, it is important to include enough detail in the description to enable the skilled person to perform the invention over the whole scope of the claims. In some cases, providing a few examples of how the invention works is enough for the requirements of sufficient disclosure to be met. This is particularly important because new matter cannot be added to an application once it is filed. In other words – if the way you describe the physics doesn’t give enough information, you have an irrevocably invalid patent.
If you would like to know more, please contact Farnaz Massoumian or another member of the Kilburn & Strode patents team. Farnaz specialised in optical microscopy before joining the patent profession.

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