Article 45 of the Chinese Patent Law stipulates that, from the date of the announcement of the granting of the patent by the patent administrative department of the State Council, if any entity or individual considers that the granting of the said patent does not conform to the relevant provisions of this Law, it or he may request the patent administrative department of the State Council to invalidate the patent right.

A PCT invention patent filed by a US-based materials manufacturing company had been granted patent rights in multiple countries, including China. In China, as a third party of the public who wanted to request the invalidation of the PCT invention patent, they entrusted IPRTOP to help them implement the invalidation process, with the goal of declaring all the claims of the PCT invention patent invalid.

This PCT patent pertains to an apparatus and a method for driving descaling media, especially liquid/particle slurry, to opposite sides of a metal sheet passing through the apparatus, thereby removing scale from the surface of the treated metal sheet. In this evaluation, judging the technical guidance—a crucial step in the 'three-step method' of inventiveness evaluation—became a focal point due to its inherent subjectivity and complexity in objectively determining inventiveness. This aspect was one of the key challenges in the case.

There were several challenges in invalidating the PCT patent: (1) The patent was a PCT invention patent entering China, with 4 independent claims, each of which was relatively long and contained many technical features; (2) In addition to the 4 independent claims, the patent also had 25 dependent claims, with a total of 29 claims, involving a lot of technical details, and it was very difficult to invalidate all the claims of the patent; (3) The PCT application had passed the substantive examination and been granted in China, Australia, Canada, UK, US, Korea, Russia and South Africa, etc., indicating that these countries had not retrieved any document that could affect the novelty and inventiveness of the PCT application, so the novelty and inventiveness of the patent were widely recognized by multiple countries. Executing an invalidation search (mainly for the novelty-inventiveness-destroying documents) was particularly daunting given the lack of effective comparative documents found in extensive searches conducted across multiple countries.

After accepting the commission, IPRTOP's agent meticulously analyzed the technical scheme of the PCT patent. This involved a thorough understanding of the claims' protection scope based on the patent's specification. A strategic search plan was formulated, continuously adjusting the search queries based on the strategy and new search results. The search was extensively conducted in both Chinese and foreign databases, requiring considerable time and effort from both our team and the client. Eventually, 4 pieces of evidence impacting the novelty and inventiveness of the PCT patent were identified. In the reexamination stage, the Patent Reexamination Board fully recognized the validity of these 4 pieces of evidence, and considered that these 4 pieces of evidence could be combined to evaluate the novelty and inventiveness of all the claims of the PCT patent. Finally, the Patent Reexamination Board made an invalidation decision, declaring all the claims of the PCT patent invalid.

Subsequently, the patentee, dissatisfied with the invalidation decision made by the Patent Reexamination Board, pursued legal action, first filing an administrative lawsuit with the Beijing Intellectual Property Court, followed by an administrative appeal to the Supreme People's Court. The result was that the first-instance judgment upheld the invalidation decision, and the second-instance judgment dismissed the appeal and upheld the original judgment. Consequently, the case was resolved with the final decision confirming the invalidation of all claims of the PCT patent. Throughout both the invalidation and administrative litigation stages, the evidence we provided was acknowledged by professional institutions as being highly reliable and capable of withstanding scrutiny, not leading to any wavering in opinions in either the invalidation decision or the administrative judgment. This outcome underscored the significance and effectiveness of the assistance we provided to our client.

Looking back at this case, whether in the invalidation stage or the administrative litigation stage, the patentee always contended that the contended of the descaling media was the main distinction between the patent and the closest prior art. They argued that the invalidation evidence D2 did not give a combination teaching, and insisted that the descaling media in D2 could not be used for the present invention. Our approach involved thorough reasoning, coupled with a keen observation that the patent's specification referenced the technical means of D2 as applicable to the disputed patent. Essentially, the specification itself acknowledged the feasibility of using D2 for the invention, rendering the patentee's arguments ineffective. Ultimately, the patentee's persistently defended points of contention failed to establish the patent's inventiveness, leading to a successful conclusion of the invalidation process.