Intellectual property rights are getting more and more attention, and they say that “the product is not moved, the patent comes first”, which also shows the importance of using patents to protect your own technology, but due to various reasons, you may encounter a situation where you did not file a patent for your technology in time, while others use the patent to sue you for infringement. So in this case, how should an effective prior-use defense be made when responding to the suit?

1. What is "prior-use right"?

First of all, the second paragraph of Article 9 of the Chinese Patent Law stipulates the principle of "first application" for patent rights: “Where two or more applicants file applications for patent for the identical invention- creation, the patent right shall be granted to the applicant whose application was filed first.” In other words, the person who first filed and was granted the patent has the monopoly of the technology for a period of time.

However, if an absolute monopoly is granted to the prior applicant, it will be unfair to the prior inventor or prior user. For this reason, Article 69 of the Patent Law stipulates five paragraph s that are not regarded as infringement of patent rights. The second paragraph clearly stipulates that “where, before the date of filing of the application for patent, any person who has already made the identical product, used the identical process, or made necessary preparations for its making or using, continues to make or use it within the original scope only” shall be deemed an infringement of the patent right, which is what we usually call the “prior-use right”.

From the above provisions, we can know that when you are sued, if you want to use the prior-use defense, you should meet the following conditions:

(1) You must have the act of implementing or preparing the identical patented technology, that is, you have started to manufacture the identical product as the patented product, use the identical process as the patented process, or have made the necessary preparations for the above-mentioned manufacturing or use;

(2) The above-mentioned manufacturing, use behavior or preparations for manufacturing and use behavior must have been carried out before the filing date of the patent, and shall continue until after the filing date. If it has been manufactured, used, or prepared for manufacturing use before the application date, but the aforesaid behavior has been stopped before the filing date, it still cannot be used as a prior-use defense.

(3) Implementation should be limited to the original scale. The prior user who continues to manufacture or use the product or process protected by the patent within the original scope shall not be regarded as infringement, and if the patent is implemented beyond the original scope, the excess part shall be regarded as infringement.

In addition, according to the judicial interpretation of the Supreme People’s Court, “made necessary preparations for its making or using” include two situations: (1) Main technical drawings or process documents necessary for exploiting the invention-creation have been made ready; (2) Main equipment or raw materials necessary for exploiting the invention-creation have been manufactured or purchased.

The original scope includes the production scale before the filing date of the patent, and the production scale that could be achieved by using the then-existing manufacturing equipment or based on then-existing manufacturing preparations.

2. How to prepare relevant evidence?

In judicial practice, to determine whether the prior-use defense is established, the following four conditions are examined:

(1) Whether the prior-use right holder has manufactured related products/using the same process or has made the necessary preparations for manufacturing/use before the patent filing date;

(2) Whether the related products/processes are the identical;

(3) Whether the prior-use technology was developed by the prior-use right holder or obtained by other legal means;

(4) Whether the prior-use right holder continues to manufacture/use within the original scope.

Therefore, the preparation of evidence is actually aimed at the above four points.

Also pay attention to the following points when preparing evidences:

l Evidence needs to fully prove the above 4 points, and the evidence needs to be true and credible, and it is best to submit proof materials issued by a national agency or an authority.

l If it is difficult to submit evidence that directly proves the above conditions, it is necessary to ensure that the relevant proof materials are sufficient, accurate and precise, and can form a chain of evidence to confirm each other without obvious defects.

3. The order of application between the prior-use defense and the prior art defense

In addition to the "prior-use right", some defendants usually think that their prior-used technology belongs to the prior art, and thus making the prior-art defense. If the alleged infringing product/process has been manufactured and sold before the filing date so that the public can know its technical content, the alleged infringing technology has constituted a prior art, and anyone can freely implement the technology in accordance with the law. At this time, there is no need to examine the prior-use defense. That is to say, when the defendant presents both the prior art defense and the prior-use defense, it should first examine whether the prior art defense is established.

Patent prior-use right is essentially a restrictive provision for patent right, which protects the interests of society and the public while reasonably protecting the legitimate rights and interests of the patentee. Although when someone preemptively files a patent and uses it to sue you, you may use the prior-use defense, but it is very demanding to use it. Therefore, we still need to improve our own rights awareness and timely use patents to protect our own technology.