IP Diagnosis: Is my medical invention patentable? Part 5

At a glance: In the present blog series a guide on patenting medical inventions is provided. Part 5 deals with treatments by surgery or surgical methods. The assessment whether a treatment or a step is surgical must be based on the correct criteria.

What’s the matter?

The assessment of whether a certain procedure qualifies as a surgical step is based on specific criteria developed and evolved in case law over the years.

Why is it important?

When trying to determine whether a method might be a surgical method and thus excluded from patent protection, it is important to apply the correct criteria to arrive at the correct conclusion.

What’s the critical point?

If you refer to outdated or obsolete criteria, your assessment might lead to the wrong conclusion and the claimed subject-matter might be excluded from patentability.

What needs to be kept in mind?

An objective determination based on the correct criteria, is particularly important before drafting and filing a patent application for a medical invention including surgical steps.

Overview

The following flowchart provides some guidance for assessing whether a medical invention is excluded from patentability. Each step of the flowchart will be discussed one by one in the present series of blog posts.

Step 3.1.1: Treatment by surgery (surgical method)

In the previous blog post the distinction between surgical methods and therapeutic methods have been discussed (here). Surgical methods practised on the human or animal body are excluded from patent protection according to the German Patent Act (PatG) and the European Patent Convention (EPC)[1].

Just one surgical step suffices to qualify the method as surgical method[2]. However, a surgical step does not have to include a curative/therapeutic purpose[3]. Further, a claim in which a surgical step has been omitted, but which surgical step inevitably needs to be performed before, during or after the claimed method steps, is implicitly covered by the claim and will lead to exclusion from patentability[4].

According to established case law a surgical step relates to a substantial physical intervention on the human or animal body that entails a substantial health risk. Whether the respective step is an invasive step or whether tissue is penetrated is not a relevant criterion[5]. Further, it is not relevant who executes the surgical step[6]. Whether a method/step can be delegated to other personnel is at best an indicator[7] and execution by a practitioner (or other medical personnel) it is not a perquisite for a surgical method/step.

Whether a physical intervention entails a substantial heath risk can be assessed based on a risk matrix[8], i.e., statistical health risk scores, or based on an abstract criterion[9] according to which a substantial health risk is beyond side effects associated with treatments like tattooing, piercing, hair removal by optical radiation and skin micro abrasion.

For example, a substantial health risk was asserted for venipuncture and the extraction of blood[10]; Continuous removal of blood, flowing through extracorporeal circuit and re-delivery (haemodialysis / apheresis)[11].

No substantial health risk was, for example, asserted for injecting magnetic resonance contrast agent into a vein[12]; retraction of a sulcus[13]; expansion of elastomeric material within the sulcus[14].

Case law example: Instrument alignment (T 2438/11)

Claim 1 of the underlying patent application EP 0 801 889 A1 related to a:

Method of aligning an instrument, in which a medical instrument to be aligned […]
[…] is being aligned with the target point (8) by means of a medical navigation (15) connected with the tracking system.

The claimed method may be practiced with medical instruments like bone drills. It is apparent, and has been pointed out by the Applicant, that dissecting the bone and drilling the bone are preparatory and subsequent surgical steps that are not part of the claimed method.

Although, the assessment that the preparatory dissecting of the bone and the subsequent drilling of the bone are not part of the claimed method was accepted by the Board of Appeal, the claimed method was nevertheless qualified as a surgical method. According to the description the aligning of the instrument at the dissected bone may be executed while the instrument is working. Since aligning i.e. moving of the instrument during the operation of the instrument at the bone, i.e., drilling of the bone, is a significant physical intervention on the body and since this intervention may cause severe harm to the patient, i.e., bone structures may break or nerves inside the bone may be injured, it also entails a significant health risk. Consequently, the claimed method, even without the preparatory dissection and the subsequent drilling, is a surgical method and excluded from patent protection.

Summary

Relying on and using obsolete (or plainly wrong) assumptions and criteria for assessing a surgical method/step before filing an application might lead to the refusal of the respective method claims. Further, the claims and the description must be drafted such that no surgical step is explicitly or implicitly included.