As a kind of intangible asset, patent has a very important characteristic, that is ,it is more unstable than fixed asset. If a patent is easily invalidated for one reason or another, it means that it is likely to lose economic value. Therefore, if enterprises want to cultivate high-value patents, the premise is to ensure the legal value of them, that is, the stability of patent rights should be strong, so that the technical value and market value of patents can be fully played on this basis.  

Whether the patent right can be invalidated is essentially related to the stability of the patent right.Article 45 of the Patent Law clearly stipulates:Where, from the date of the announcement of the grant of the patent right by the patent administration department under The State Council, any entity or individual considers that the grant of the patent right is not in conformity with the relevant provisions of this Law, it may request the Patent Reexamination Board to declare the patent right invalid. Article 47 of the Patent Law specifies the effect of invalidation: a patent right declared invalid shall be deemed to have ceased to exist from the beginning.

Then how to improve the stability of authorized patents, the following will be introduced from the protection scope of claims and the stability of patent rights:

Firstly, the applicant should take care to avoid pursuing unreasonably wide protection.The applicant should realize that the maximum protection granted by a patent right depends not on the applicant's will, but on the degree of innovation of the invention.China's patent law has stipulated various measures to restrict the scope of patent protection, among which novelty and creativity are the most important ones. From the perspective of seeking a wider range of protection, the less technical features recorded in the claim, the better.  However, the less technical features recorded in the claim, the more "superior" the technical terms expressing these technical features, the more likely it is to be denied its novelty and creativity by the existing technology. Therefore, from the perspective of good stability of patent right, the more technical features recorded in the claim, the better. However, the more technical features are recorded in the claim and the more specific the technical features are expressed, the smaller the scope of patent protection is determined. Therefore, when defining the protection scope of claims, it is necessary to take both into account to achieve a reasonable balance.  

Secondly, in the process of writing, the specification should be as detailed as possible. If the claim wants to generalize a technical feature to a superior concept, the specification should give an appropriate number of embodiment to prove that the technical solution adopts the commonality of all inferior concepts contained in this superior concept, that is, the same expected effect can be achieved. If it is uncertain whether all the inferior concepts contained in this superior concept can achieve the purpose of the invention and achieve the desired effect,in the process of writing claims, there should be at least one technical scheme of subordinate claims that can be supported by the specification in order to advance or retreat. As it is in the follow-up procedure, there are strict requirements for the modification of claims.The specific ways of modifying claims in invalid procedures are generally limited to the deletion of claims, the deletion of technical schemes and the further limitation of claims(One or more technical features recorded in other claims shall be added to the claim to reduce the scope of protection ).  

To sum up, the clearer the technical features of the claim and the more reasonable the protection scope of each claim in the claim, the higher the probability of the patent being maintained valid.