At the beginning of the new year, we learned that the German Federal Patent Court had ruled in favor of OPPO, declaring their 5G standard essential patent (SEP) EP3445093 fully valid. This patent was utilized by OPPO in a legal battle in Germany, alleging that Nokia's product had infringed the patent. OPPO further sought an injunction. Tang Hai is credited as the inventor of this patent. A quick search in patent databases reveals that OPPO has filed more than 440 patent application families worldwide, with Mr. Tang being one of the inventors.
Before drafting this article, on January 24th, OPPO announced a global patent cross-licensing agreement with Nokia, encompassing SEPs in 5G and other cellular communication technologies.
While we are heartened by the increasing international influence of Chinese tech companies in the field of SEPs, we are also inclined to gather insights from the European examination history of this patent. Drawing from our prior experience in intellectual property practice within top-tier IP agencies and companies, we aim to offer guidance to patent practitioners, especially in drafting SEP applications. Naturally, this analysis might be susceptible to hindsight bias. Still, we'll strive to maintain an objective stance, reconstructing the considerations when drafting and providing recommendations for patent drafting.
EP3445093's corresponding PCT application was made public in January 2018 and entered the EPO phase on November 13, 2018. The claims were streamlined from 50 to 15, likely for cost-saving reasons. Among them, independent claim 1 describes a method for transmitting information at the sender's end, while independent claim 3 describes a method for receiving information at the recipient's end. Independent claims 14 and 15 refer back to claims 1 and 3, respectively, for claims for the device.
On February 18, 2019, the EPO issued a supplementary search report, indicating issues with claim 4's clarity and lack of novelty in independent claims 1, 3, 14, and 15 compared to prior art documents 1, 2, and 3, with dependent claims 2, 4-13 lacking novelty or inventive step. Responding to this, the applicant submitted amended claims on September 12, 2019, integrating additional technical features of original claim 8 into independent claims 1 and 3, introducing two new claims 14 and 15 for devices aligned with method claims 1 and 3, and addressing clarity issues in independent claim 4.
On January 7, 2020, the EPO issued a first examination opinion, noting that the amendment to claim 4 exceeded the original disclosure and highlighting clarity issues in claims 1, 3, 4, 14, and 15 due to the term "dedicated system information." Independent claims 1, 3, 14, and 15 were also found to lack novelty, potentially implying the prospect for other claims to be granted.
In response, the applicant submitted amended claims on May 14, 2020, removing the newly added technical features in claim 4, which was initially used to respond to the supplementary search report. The applicant also incorporated the limitation of the term "dedicated system information" into independent claims, removing previously added technical features from independent claims 1 and 3 (corresponded to the original claims 8), supplementing specific features related to transmitting scheduling information and system information to claims1, supplementing specific features associated with transmitting and receiving information to claims 3, and making similar adjustments to device claims 14 and 15.
On November 6, 2020, the examiner issued a notification indicating the impending grant of European patent rights, with the formal grant decision being officially issued on January 21, 2021.
Three versions of claim 1 are provided below:
From the examination history outlined above, it's clear that there were some challenges encountered in addressing the supplementary search report and the first examination opinion. The applicant even shifted their response strategy, for instance:
This change might have been prompted by highly targeted examination opinions from the examiner or due to considerations of patent alignment with standards.
However, regardless of the reasons, the significant flexibility exhibited by the applicant in amending the claims, ultimately leading to the grant of the SEP application and its suitability for European patent litigation, underscores the meticulous groundwork laid during the drafting of the specification.
Examining the original public version of this PCT application reveals that, firstly, it provides a method for transmitting information, including:
Regarding this aspect, the specification details 13 possible implementation scenarios, elaborating on the content of "system information" and "scheduling information" in each scenario. Specifically:
In response to the first examination opinion, these features were added to claim 1.
According to the specification, secondly, it provides a method for transmitting information, including:
Regarding this aspect, the specification also details a total of 10 possible implementation scenarios, where:
In response to the first examination opinion, these features were added to claim 3.
Additionally, the specification's fourth, fifth, sixth, and seventh aspects describe the devices and systems for transmitting information, while the eighth and ninth aspects describe the computer-readable media.
It's evident that the patent's inventors/agents conducted comprehensive considerations, including methods, devices and schemes for both information transmission and reception. Specific implementations for information transmission and reception were refined, expanded, and associated, conceptualized into various technical features. This makes it highly probable that various equivalent alternatives would fall directly within the protection scope of the claims. Moreover, a considerable number of specific implementation scenarios can be obtained through the combination of these technical features. Thus, subsequent modifications to the claims have ample room for maneuver.
Even in the context of clarity-related examination opinions, as multiple implementations in the specification describe the content and functionality of dedicated system information from different perspectives, the agents can easily limit the scope by extracting features from the specification in their responses to the examiners.
From the perspective of patent drafting, undoubtedly, the layout of the claims and the support and expansion provided by the specification have been exceedingly successful.
Our recommendations
Indeed, obtaining a SEP is no walk in the park. Patent applications need to pass rigorous substantive examination and align with the standards they aim to cover.
According to the "Global 5G Standard Essential Patents and Standard Proposal Research Report (2023)" released by the China Academy of Information and Communications Technology, the overall acceptance rate of 5G proposals is approximately 33%. Among them, the acceptance rates for TSG RAN, TSG SA, and TSG CT proposals are 23.2%, 52.6%, and 72.9%, respectively.
It's clear that the road to success in this field isn't something you can summarize in a few sentences. Nevertheless, we'll shed some light on drafting techniques for SEPs.
To explain further, let's consider a scenario where inventors can participate in meetings held by standard-setting organizations and learn about the key technical directions of a certain standard. When drafting a patent application, inventors predict that the standard's technical solution includes features A, B, C, and D, where A is based on existing technology, while B, C, and D present patentable opportunities.
The patent attorney should help expand the scope during the patent application process. Different patent attorneys may put in varying degrees of effort. For example:
Suppose both patent attorneys incorporate all these detailed features into the patent application. In that case, the first patent attorney's drafted claims could cover 2*2*2=8 implementation methods, while the second patent attorney's drafted claims could cover 5*8*2=80 implementation methods.
On the other hand, during the standard-setting process, there are extensive discussions, voting, and negotiations among stakeholders. Even if a standard proposal is accepted, the final standard released may differ significantly from the initial proposal. This is because negotiations among stakeholders can lead to modifications or optimizations of the standard proposal.
Given these factors, it's evident that the expansion of the second patent attorney can help the applicant respond adeptly to examination opinions and modify claims while significantly increasing the probability of the technology being included in the standard.
Ultimately, it's hard to predict whether a technology will become a standard, but the applicant can recognize the efforts of the patent attorney. Moreover, the patent attorney's expansion or elaboration of each technical feature may directly influence whether the patent application ultimately becomes a SEP.
In summary, here are some suggestions for patent attorneys when drafting SEPs:
We strongly recommend that patent attorneys comprehensively describe various implementation scenarios in the specification. This offers significant flexibility for amending claims during the examination stage, ensuring they stay within the original scope and consistently receive support from the specification. Moreover, and more importantly, regardless of the choices or improvements made in the developing standard technology, as long as we grasp the main technical direction of the standard when filing the patent application and include all conceivable combinations of solutions in the specification, it greatly facilitates the alignment of the final version of the standard with this framework.
Drawing from our experience in patent application, invalidation, mapping, and IP management at corporate levels, the cultivation of SEPs requires close cooperation among the standard development department, corporate IPR, and third-party patent attorneys. Compared to regular patent applications, applications for SEPs have stricter timeliness requirements and require a forward-thinking drafting strategy. The standard development department needs to promptly keep abreast of standard-setting trends, and corporate IPR needs to update patent attorneys in making adaptive modifications to the claims. Therefore, it dramatically tests the communication and coordination among the three parties.
We can only provide general suggestions for writing SEPs in this article. However, there are many specific experiential techniques worth further exploration in practice. Additionally, as of the writing of this article, the information on invalidation litigation for such patents and related records has yet to be made public, but we will continue to monitor it.
PurpleVine has extensive experience in SEP applications. Reach out to our SEP team members if you have any questions.
Author: Xing WANG
Xing has 14 years of experience in intellectual property and 4 years of experience in machine vision product development. He has provided intellectual property services for companies such as Synaptics, Panoptis, Carestream, NIO, and China UnionPay. He has frequently been involved in patent invalidation procedures and administrative litigation related to SEPs. He also has rich practical experience in corporate intellectual property management, SEP benchmarking, and open-source software compliance. Before joining PurpleVine, he worked for Shanghai Baosight Software Co., Ltd., Shanghai Lungtin Law Firm, China Patent Agent (HK) Ltd., and Zeku Technology (Shanghai) Co., Ltd. Xing holds a Master's degree and Bachelor's degree in Engineering from Tongji University in Shanghai. He is qualified as a patent attorney in China and has a legal certificate in China. Xing can be reached at xing.wang@purplevineip.com.