How to achieve a European Patent Office technical effect in mathematical healthcare patents
More light is shed on how to achieve a European Patent Office technical effect in mathematical healthcare patents in a recent Board of Appeal case.
A patent using maths on blood sample data survived opposition in European Patent Office (EPO) Board of Appeal case number: T1423/22.
It is interesting to compare a few recent EPO Board of Appeal decisions in this field in the following table.
T1423/22 board 3.3.08 G1/19 was referred to | Patent survived opposition | Comparing a standard value with a value computed from an equation using values measured from blood samples (with the implied aim of diagnosing renal disease) |
T 1741/22 board 3.5.05 G1/19 was referred to | No inventive step due to no credible technical effect produced by deriving additional data from medical measurements | Analysing glucose monitoring data indicative of a glucose level in a bodily fluid, where minimum and maximum glucose values are determined and displayed |
T 2681/16 board 3.2.02 G1/19 was referred to | Found to be inventive | Analyse blood glucose data points using maths and display risk category |
T1910/20 board 3.5.05 G1/19 not referred to CMS | Law-Now | AI in healthcare inventions – technical or not technical? | No EPO technical effect | Displaying patterns such as cluster centres in glucose data |
Claim 1 of the patent in case T1423/22 relates to a method for estimating the glomerular filtration rate (GFR) in an animal subject. The GFR is used to determine renal function of an animal subject. The claim comprises three steps:
- measuring the concentration of free symmetrical dimethylarginine (SDMA) in a blood sample from the subject;
- measuring the concentration of creatinine in a blood sample from the subject; and
- comparing a value resulting from an equation comprising the product of the concentration of creatinine and the concentration of free SDMA to one or more standard values that correlate to glomerular filtration rate in the animal subject.
Inventive step
The BoA found step (iii) to be non-technical as it relates to a mathematical operation as it is multiplication of two measured biomarker values together, and to a mental act of comparing the value of the resulting product to one or more standard values.
The distinguishing features
D1 differs from the claimed method in the non-technical step (iii).
It was argued that the step (iii) contributes only to the solution of a non-technical problem, e.g. a problem in a field excluded from patentability. It was argued that step (iii) is:
- limited to feeding the results of measurement steps (i) and (ii) into an equation and comparing the resulting value with standard values; and
- mere comparison of a calculated value to the standard values and did not contribute to an estimation of the GFR since no instruction was given in the claims as to how.
In the reasons for the decision the Board of Appeal referred to case G1/19 which states that if a claimed invention consists of a mixture of technical and non-technical features and has a technical character all of the features that contribute to the technical character (technical purpose) are to be taken into account in the assessment of inventive step. This is the case even if these features are non-technical features.
In paragraph 18 of the reasons the Board of Appeal found that the claimed method has a technical character (i.e. solves a technical problem) of estimating the GFR, a clinical parameter relevant in renal diseases, based on measuring the blood concentrations of two markers (SDMA and sCr). The non-technical step (iii) contributes to solving this technical problem along with the rest of the claim, because the GFE estimate for an animal subject is determined by the comparison of the calculation of a product of SDMA and sCr which were measured in steps (i) and (ii) respectively and one or more standard values that correlate to the GFR.
In paragraph 19 of the reasons the Board of Appeal noted that the claim lacks an explicit link of step (iii) to the actual estimation of the GFR. However, the Board of Appeal found that despite this deficiency, the skilled person immediately understands from the wording of the claim that the comparison to standard values, which correlate to a particular GFR, directly and necessarily leads to the estimation of the GFR.
Comment
In paragraph 21 of the reasons the Board of Appeal goes on to note that sufficiency of the claim was not assessed, since this had not been raised as an objection by the opponent. The Board of Appeal states that “not achieving this effect [estimating GFR in an animal subject] by the steps of the claimed method would result in a lack of sufficiency of disclosure”.
Therefore patent stakeholders will do well to take into account sufficiency at all stages of the patent process.
