EP 3 332 729 A1 relates to a medical tracking system comprising at least two sensor devices which are independently manoeuvrable and can be positioned in a fixed position relative to targets and a method of determining relative position between two sensor devices of a medical tracking system.
Brief outline of the case
The present application was refused as the ED considered that claim 7 related to a prohibited method under Art 53(c).
The applicant appealed and the board held that claim 7 did not infringe Art 53(c).
The applicant’s point of view
The invention as defined in claim 7 aimed at providing a method of determining a relative position between two sensor devices. This could be achieved without a surgical step because it was not necessary to attach a sensor device to the patient. None of the claimed steps defined or encompassed a physical activity or action that constituted a method step for treatment of a human or animal body by surgery.
The fact that the claimed method could be performed during a surgical intervention was irrelevant as there was no functional link between the claimed method and any effects of a surgical nature that would occur during the intervention. Therefore, the method did not count as a method for treatment of the human or animal body within the meaning of Art 53(c).
Since the step of attaching a sensor device to an anatomical structure was not essential, there was no violation of Article 84 EPC either.
The board’s decision
The patent application relates to medical tracking. Typically, a medical tracking device is used to detect the position of markers which are attached to targets, such as objects or anatomical points to be tracked.
The board disserted heavily on the difference in G 1/07 between “comprises” and “encompasses”
The board held that the boards of appeal have often referred to what is “encompassed” or “embraced” by a claim or feature to describe the subject-matter that is included within its scope, see e.g. Reasons 7 of G 3/95, Order of G 1/15 or Reasons 116 of G 1/19.
With this meaning, a generic feature encompasses all conceivable implementations that fall within its scope. Similarly, the subject-matter of a dependent claim within the meaning of R 43(4) is necessarily encompassed by the claim on which it depends.
G 1/07 uses the verb “encompass” on several occasions, most prominently in points 1 and 2a of the Order.
1. A claimed imaging method … which comprises or encompasses an invasive step …
2a. A claim which comprises a step encompassing an embodiment which is a ‘method for treatment of the human or animal body by surgery’ within the meaning of Art 53(c) cannot be left to encompass that embodiment.
The board held that for almost any method claim, it is possible to conceive of a more specific claim (i.e. a dependent claim, comprising an additional step that is surgical. This more specific claim would fall under the scope of the initial method claim which did not recite this additional surgical step.
Therefore, if “encompass” were used with the above meaning, virtually all method claims would encompass a surgical step and not be allowable under Art 53(c). It is therefore clear that “encompass” in G 1/07 is not used with the same meaning as discussed above.
For the board, G 1/07 uses the term “comprise” in relation to a step that is explicitly recited in a method claim. By contrast, G 1/07 uses the term “encompass” with regard to an embodiment or step that the patent application mentions as a specific implementation of a more generic claimed method step.
With the meaning of “encompass” as used in G 1/07, a claimed method encompasses steps of its dependent claims in so far as they define specific embodiments of one or more steps comprised in the claimed method. However, in this board’s view, additional steps that are defined only in the dependent claims are not necessarily encompassed by the independent claim.
The board added that the principles of G 1/07 can be extended to steps which are claimed implicitly rather than explicitly, and referred to Reasons 2.1 of T 1526/17; Reasons 2.1.1 of T 1075/06; Reasons 2 of T 1631/17; Reasons 2.2.1- 2.3 of T 318/21; Reasons 2.3 of T 1005/98, prior to G 1/07.
In this context, implicit steps are those that a person skilled in the art would consider to be necessarily implied as an integral part of the claimed method. Consequently, they are comprised in the claimed method.
Claim 7 – Article 53(c) – Attachment to a bone
The board accepted that a step of directly attaching a sensor device to a bone is to be regarded as a surgical step. However, claim 7 does not explicitly comprise any step of attaching a sensor device to a target, nor any other step encompassing – within the meaning of G 1/07 – attachment of a sensor device to a bone.
Taking into account G 1/24, Order, the description does not suggest that the step of attaching the sensor device to a bone is part of the claimed method.
Rather, the last paragraph states that the invention “solely relates to the step of navigating, tracking and verifying by acquiring and analysing data”.
The ED referred to the fact that claim 8 of the then MR specified that “each sensor device is attached to a target”. It is questionable whether the fact that a dependent claim defines an additional step allows any conclusions to be drawn about which embodiments are encompassed by the steps of the independent claim. In any event, the question is moot since former dependent claim 8 has been deleted in the current MR.
The method defined in claim 7 can be carried out and the relative position between the two sensor devices determined regardless of whether or not each sensor device is attached to a target. For example, the claimed method could be used to determine the relative position of two freely movable sensor devices that are not attached anywhere, e.g. carried by a user, or that are attached to medical hardware such as movable imaging scanners.
Accordingly, the claimed method does not require one or both sensor devices to be attached to a target. At least for this reason, attachment of the sensor devices to a target, such as a bone, is not implied as an integral part of the claimed method, i.e. it is not an implicit feature of the method.
Movement of an exposed bone
The application describes a workflow involving moving the exposed tibia relative to the exposed femur using the knee joint while calculating the relative position of the sensor devices. Pivoting the exposed bone constitutes a surgical step, see T 1526/17, Reasons point 2.1.
Claim 7 concerns a method of determining a relative position between two sensor devices. In contrast to the situation in T 1526/17 or T 318/21, the sensor devices need not be moved in order for their relative positions to be determined. Instead, the method concerns a passive, one-time determination which does not rely on any motion or acceleration by the sensor devices or the targets. It is thus a situation comparable, in respect of the movement of a bone, with determining the position of the distal end of a bone guide wire in the case on which T 836/08 was based.
It follows that the method of claim 7 does not comprise a step of moving the sensor devices, either implicitly or explicitly. Therefore, the claimed method does not comprise or encompass movement of an exposed bone.
In conclusion, the method of claim 7 did not comprise or encompass any surgical steps. Consequently, it does not constitute a method for treatment by surgery within the meaning of Art 53(c).
Comments
The present board is really playing with words. It is a mere apodictic statement when the board alleges that virtually all method claims would encompass a surgical step and not be allowable under Art 53(c). Where the board gets the idea that it is clear that “encompass” in G 1/07 is used with a different meaning?
The board took pretext that claim 8 as originally filed relating to the fixation of a sensor on the bone was deleted to consider claim 7 not relating to a surgical method.
Here are excerpts of the original description:
§ [0022]: “As an example, the target is a bone and the coordinate system is defined by the bone….. In an exemplary implementation, two sensor devices, each comprising an orientation sensor, are rigidly attached to two adjoining bones which are connected via a joint…… In another exemplary implementation, one sensor device is attached to a cutting slot of an adjustable cutting block, the base of the adjustable cutting block being rigidly attached to a bone. The second sensor device is rigidly attached to the bone. The orientation sensor data of the first sensor device is then converted into orientation sensor data given in a coordinate system defined by the bone.”
§ [0029]: “The present invention further relates to a method of determining a relative position between two sensor devices of a medical tracking system.”
§ [0033]: “In a preferred embodiment, each sensor device is attached to a target, such as an anatomical structure like a bone, a medical instrument or a part of an operation room infrastructure”.
§ [0036]: “The present invention further relates to a method for determining a mechanical property of a joint between two bones….”
§ [0039]: “The present invention further relates to a method for aiding the adjustment an adjustable cutting block comprising a base and a cutting slot which is adjustable relative to the base….”
[0041] “The current alignment of the cutting slot can be continuously compared to a desired alignment, which might be pre-planned using a 3D scan of the bone and/or the mechanical property of the bone which is determined as explained above.”
[0042] “After the cut has been performed using the cutting block, the cutting surface can be verified by placing a defined surface of the second sensor device on the cutting surface”.
§ [0044] “As another option, anatomical data from a previous diagnostic step or other examinations are used to increase the accuracy of the determined relative position and/or to limit the degrees of freedom when the relative position is determined.”
It is thus hard to follow the board when it says that the method as exemplified and disclosed neither comprises nor encompasses a surgical method. All the examples relate to a surgical method.
When “consulting” the description under G 1/24, the board must have had very large blinkers to say the least. Claim 1 which has not been queried by the ED related to a medical tracking system….
In view of the description and order to clarify the situation, the method claim should have comprised a disclaimer as envisaged in the last § of the description. Such a disclaimer is perfectly allowable under G 1/03 or G 1/16.
Comments
2 replies on “T 0941/24-Not a medical method?”
This decision has long been overdue, and I’m sure it’s welcomed not just by me but also by others practicing in the field of medical devices.
Without making it quite explicit, the Board draws on the distinction between the claim’s subject-matter and its scope of protection, something that seems to be increasingly difficult for most Examining Divisions. The claimed subject-matter is the set of features defined as mandatory in the claim. It forms the core of the claimed scope, but it is not identical thereto. The scope of protection is more than the claimed subject-matter, it encompasses all embodiments realizing the mandatory features and potentially including further features. In the case of a method, the scope extends to methods including addition steps that are not recited in the claim as mandatory. The Board is absolutely right in that for the exclusion under Art. 53(c) EPC to apply, it can’t be sufficient that the claimed scope covers additional steps that might be surgical in nature. For Art. 53(c) EPC to apply, the claimed subject-matter (i.e. the claim’s mandatory set of features) has to include a surgical step. This can be an implicitly required step, neccessary to perform the claimed method. It can be an explicitly recited surgical step. Or it can be a step that is not explicitly surgical in nature, but which has specific implementations in which this step is surgical in nature. The latter is exemplified in T0318/21, in which the claim was directed at a “Verfahren zur Bestimmung eines Position und einer Orientierung eines Endoskops in einem Hohlraum”. In some examples, the “Hohlraum” or cavity was a bodily cavity. The claim thus explicitly required the method to take place in a cavity, or implicitly required the step of to introducing the endoscope into a cavity. In some examples, this cavity was a bodily cavity, and the mandatory features of the independent claim thereby “encompassed” a surigcal step.
It is therefore irrelevant for the assessment of Art. 53(c) EPC that the application discloses examples, which by virtue of additional steps being present which are not mandatory in the claim, might fall under Art. 53(c) EPC.
@ Max Vier,
Although I understand your point of view, I am not sharing it.
I have been working for a long time in this field as director, and I maintain that the method may “encompass” a surgical step.
When consulting the description under G 1/24, this is blatantly apparent. It is thus by no means irrelevant that the disclosure relates to a method which can be applied to the human or animal body.
In the present case, I would have advised my examiners to request that a clear disclaimer under G 1/03 or G 1/16 is added to the claim in order to exclude any application on the human or animal body. Such disclaimers are expressly provided for such a situation. There is enough material in the original disclosure justifying the exclusion of methods under Art 53(c) by a disclaimer.
With a disclaimer the situation would have been clear. Relying on an shoddy interpretation is not the right way to deal with this kind of claims.
Let’s wait and see if an opposition comes. If yes, a disclaimer would be the right way to go.
As far as T0318/21 is concerned, it was without doubt a method falling under the prohibition of Art 53(c). Endoscopy applied to the human or animal body has always been considered as surgical.
However, endoscopes can also be used in industry, e.g. for inspecting turbines. But this needs to be originally disclosed next to the medical application.