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Discussion about methods of diagnosis or treatment in Chinese Practice

Eric Zhiguang GENG
Patent Attorney
Electrical Engineering Department
Welcome to Linda Liu & Partners on air!
My name’s Eric Geng and I’m a patent attorney from the department of electronics in Linda Liu & Partners. It’s my great honour to post this talk about the methods of diagnosis and treatment in Chinese practice, and hope you’ll find it useful.
As far as I know, the methods of diagnosis and treatment are not patentable in Europe according to Article 53 of the European Patent Convention; while in the US to grant a patent on methods of diagnosis and treatment is possible. The situation in China is similar to that in Europe, the methods of diagnosis and treatment are not patentable, according to Article 25 section 3 of the Chinese patent law. It says:
For any of the following, no patent right shall be granted: (1) scientific discoveries; (2) rules and methods for mental activities; (3) methods for the diagnosis or for the treatment of diseases; (4) animal and plant varieties; (5) substances obtained by means of nuclear transformation; and (6) designs of two-dimensional printing goods, made of the pattern, the colour or the combination of the two.
Two reasons behind this prohibition of patentability are given in the examination guidelines, the first is that, for humanism, a medical staff should never be restricted in choosing any possible approach for diagnosis and treatment; and secondly, as the object of any diagnosis or treatment is definitely an animal or human being, such a method is deemed as having no practical applicability. I ‘d like to further point out that, in a Chinese notification of office action or decision of rejection, the reason for rejecting a method of diagnosis or treatment is always that, the method belongs to a subject matter that is not patentable as listed in Article 25 of the Chinese patent law, and that’s it. You will never find any comment on its practical applicability, although it is one of the two reasons behind that Article 25.
More explicit and specific definitions on the methods of diagnosis or treatment are given in the Examination Guidelines. Where it is said, “Methods of diagnosis refer to the processes of identifying, studying, and determining the cause or focus of diseases on living human or animal bodies”, and “Methods of treatment for diseases refer to the processes of intercepting, relieving or eliminating the cause or focus of diseases so that the living human or animal bodies may recover or gain health or relieve pain”. These definitions are very important because most of our arguments in this regard are based on the above definitions.
Now I would like to share some experiences and practical tactics on the filing and examination in China on the applications which may involve methods of diagnosis or treatment.
From the above definitions, it can be seen that, firstly, both the methods of diagnosis and the methods of treatment must be applied on living human or animal bodies. Secondly, the direct purpose of the method is a key consideration when determining a method of diagnosis or treatment.
Therefore when drafting a method claim or amending a claim during the examination, it would be wise not to include any operation on a human body, or any effect to be realized on a human body. For example, if we have a method claim about improving the image processing which could be part of x-ray diagnosis, then a step of “receiving an x-ray image of an area of interest” will be enough, but try not to say “apply x-ray radiation onto a part of a patient body to obtain an x-ray image”. Then the method can be explained as a pure image processing, where the object of the method is the image and the direct purpose is to get or highlight, for example, a certain feature of the image. Then it does not belong to a method of diagnosis.
And we may notice that, in most modern diagnosis approaches, intermediate parameters or results are usually generated, and a method claim can be drafted as referring to the intermediate parameters or results, rather than the ultimate diagnosis. In the above example, shadows in the x-ray image may suggest a focus of disease and could be used for diagnosis. But a method of extracting or highlighting such a shadow from an x-ray image is perfectly patentable in China, because, as given above, the method is an image processing applied on the x-ray image, and the resulted shadow is obviously an intermediate result, rather than determining the focus of disease. Again, please bear in mind that, the ultimate diagnosis must not be mentioned in the claim. For example, wordings like “a shadow or an x-ray image for identifying a tumour”, of course should be avoided.
Similar to the methods of diagnosis, the determination on methods of treatments requires that, the method must be applied on living human or animal bodies, and the purpose of the method is  to intercept, relieve or eliminate the cause or focus of diseases, to make the living human or animal healthy.
In Chinese practice, there is plenty of room for methods that are not applied on living human body and do not directly aim to eliminate the focus of diseases or make the living human or animal bodies recovered, even though these method may be therapy-related. For example, a method of ablating a tissue with radiation will not be allowed, but we can still seek for a patent protection on the method of directing such a radiation. Again, first of all, the potential usage of the radiation in ablating a tissue of human body must not be mentioned in the claims. In turn, the method can be drafted as a pure control method, with an object defined as for example a device for moving or activating of the radiation source, so as to realize a better controlling of the radiation beam. Then the method has nothing to do with a living human or animal body or the healing of the body, and the method then becomes patentable.
Let’s go on with the example of radiation for ablation. On the other hand, it will be very difficult to make any argument, if the control of the radiation requires feedback about the effect happening on the human body; for example the control of the radiation may rely on an updated depth of the ablation; that means the method must be applied on a human body, together with feedback about the treatment effect. I’d like to call this a “man-in-the-loop” method, and from my experience, it’s very difficult to get this “man-in-the-loop” method allowed.
In sum, to avoid rejections on methods of diagnosis or treatment in Chinese practice, we should always remember the two critical factors as given above. Just try to draft a method that can be implemented independently from a living human body, which means, firstly, the object of the method is not a living human or animal body, and secondly, the goal of the method is not to identify or eliminate a disease. For example, methods for obtaining an intermediate physical parameter, or methods for controlling or setting a device, will be deemed as patentable subject matters in Chinese practice.
Generally speaking, in practice the Chinese examiners tend to challenge any potential medical-related method in examinations and we often receive rejections on methods of diagnosis or treatment; but by following these suggestions, most of the rejections can be overcome and patent protections on these method claims can be eventually granted.
And at the end, i just would like to give a remind on one very risky situation i have ever seen in practice. Maybe because of the different requirements in different countries, some medical related international applications, when entering the Chinese national phase, have method claims only. This is very dangerous because in China, we can hardly introduce any new independent claim after the issue of the first office action. That means, if we have method claims only and all of them are rejected in an office action, then at that stage, we cannot introduce any device claim anymore, but have to keep going on with the method claims, and if the examiner insists his or her opinion, there would be a final rejection. So we always suggest the applicant that at least one device claim should be included in the application, to ensure that at least there is one set of claims that is a patentable, to at least keep the application in power.
The above are some experiences and conclusions from my own practice. Hope this can be helpful for your Chinese application. And if you would like more discussions about the protection on methods of diagnosis or treatment in China or in your local practice, you are always welcomed. You can find me on the Linkedin or via
As a leading patent law firm in China, we are always glad to help.
See you next time!
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