With the development and popularization of the Internet, kinds of information published on the Internet have become a new form of statutory evidence. According to the provision of the Patent Examination Guidelines, the information existing on the Internet or other online databases are also published publications. It has verified the status of network evidence as evidence of prior art.

A few of the evidence rules in the patent invalidation procedure are not exactly the same as the ordinary civil litigation, and there are certain peculiarities. For example, as evidence of the prior art, they need to be disclosed and is easily available for the public, that is that is "if you want to know, you will know." This kind of information may be from the company website publishing information about the patented products involved in the case, news media websites, interactive media websites, such as Weibo, Twitter, Facebook, and E-commerce platforms (Such as Taobao, eBay, Amazon, etc.).

Under most circumstances, the publisher can edit and modify the information published on the network to cover the original information. The network evidence is uncertain and easy to adjust, and the trace of the modification is difficult to find, so it is also difficult to identify the network evidence. Therefore, it is necessary to consider various situations comprehensively to judge the authenticity and publication time of the network evidence before deciding whether to adopt it.

The evidence from the network is comprehensively considered in terms of their qualification, credit, and management status of the source of the evidence. Generally, notarization of the proof by a notary is adopted to preserve the network evidence, but those from overseas are also adopted but shall be notarized and legalized in a different procedure. 

The combination of "Baidu Wenku" and a certification letter from Baidu is using evidence in China, which is utilized as the existing technology or existing design of the patent involved. In a current invalidation case (invalidation decision number 41979), the applicant of invalidation submitted the evidence of Baidu Wenku and certification letter, and the patentee appeal with the following cross-examination opinions: "There are two types of free documents uploaded to Baidu Wenku: non-confidential documents and confidential documents. Non-confidential documents are open for the public, and confidential documents are only open to the uploader according to different settings. And the status of the document can be freely converted between confidential and non-confidential without changing the upload time, so if there is no other evidence to support, it cannot be confirmed by Baidu Wenku and the certification letter that the document was published before the filing date of the patent application involved. "The cross-examination opinion also said that although the upload date of the material in Baidu Wenku is earlier than the patent filing date, there is no other evidence to prove that the documents involved were non-confidential before the patent filing date. It cannot be ruled out that the documents involved before the patent filing date were confidential documents or not.

In the Invalidation Decision, No. 41979 made on October 28, 2019, the Department of Reexamination and Invalidation of the CNIPA gave the following decision opinion: Although the documents in Baidu Wenku are in public and non-confidential status, the right holder could not provide that the status of evidence had been changed or not. Secondly, Baidu Wenku serves as a document sharing platform, for the basic purpose of users to upload documents on the platform, it is in the low possibility that to set permission when uploading the documents, or change the permission after uploading the documents. Considering the evidence, in this case, is a product manual, which is not very classified, and the document has a high score, and a certain number of views and downloads. Hence, it was more likely to be disclosed to the public when it was uploaded. Moreover, the publication time recorded in the document is much earlier than the upload time of the document, and there is no obvious illogical. Therefore, in the absence of evidence to the contrary, the Panel believes that the above-mentioned documents have been in a non-confidential status since the date of publication with high probability, which has constituted disclosure in terms of patent law.

From the invalid decision of the above case, it shows that the court accepted the evidence with high probability. Not only discussed the nature of Baidu Wenku in the case but also discussed whether the content of the document confidential is confidential. In addition, the views displayed on the document shows that the possibility that the evidence is confidential is low.

The determination of the authenticity and publication of network evidence is core work in the trial of patent invalidation cases, and also the basis for the judgment of existing technical solutions or designs, which directly impact the final result. The applicant of invalidation should, within the time limit for adducing evidence of the invalidation procedure, enrich the portfolio of network evidence and other evidence as much as possible to form an evidence chain which can mutually verify each other, so as to improve the credibility of the evidence and the possibility of being adopted.

It's suggested to file the patent application well before disclosing the product, in case the disclosure of the product impacts the novelty and inventive step of the patent application, and also increases the risk of being invalidated after grant.