When Standards Evolve: How China Judges Inventiveness in Next-Gen Tech Patents

Starting in 2023, Datang Mobile, one of the key players in China’s telecom standardization efforts, initiated infringement proceedings against Samsung in China, Germany, and the US. Samsung responded by filing multiple invalidation petitions in several jurisdictions, including China, the United States, and Europe. The case discussed below is one of above-mentioned invalidation cases in China, and was selected as one of the Top Ten Reexamination and Invalidation Cases of 2024 by CNIPA as

“a typical patent case in the field of communications involving standards evolution in that its assessment of inventiveness provides guidance for this type of case.”¹

Legal & Technical Focus

The patent involved is titled “Carrier Aggregation Feedback Method, Device, and System,”² owned by Datang Mobile³. Carrier aggregation (CA) is a key technology introduced in LTE-Advanced (4G) and further developed in LTE-Advanced Pro (sometimes referred to as “4.5G”) and 5G. The patent concerned the evolution from 4G intra-band CA to 4.5G inter-band CA.

The core issue of the invalidation request raised by the petitioner, Samsung⁴, was whether the patented invention—designed for inter-band CA scenarios—was obvious in view of prior art based on earlier intra-band CA standards.

Key considerations around the obviousness assessment included:

1. The petitioner argued that combining 4G prior art with 4.5G references rendered the claim obvious.
2. The patent’s central distinguishing feature was the method and system for determining the maximum number of subframes requiring feedback (M) based on carrier configurations from the system information tables—rather than from actual usage data as in the prior art.
3. The Patent Office determined that the prior art did not disclose or suggest deriving M from configuration tables, nor did it provide a clear technical motivation for such a modification.
4. Therefore, the invention solved a new problem specific to inter-band CA scenarios and achieved a technical effect of improved feedback efficiency.

Ultimately, the patent was maintained in amended form, and the parties later reached a global settlement.

Guidelines from the Examiners

In a subsequent CNIPA article⁵, the examiners in charge summarized their methodology for reviewing the inventiveness of the disputed patent. This methodoloy not only shows the CNIPA internal standards, it also practically serves as a guideline for assessing inventiveness of similar type of cases in the future.

Step 1: Determining, relative to the prior art, in which aspects the intergenerational change of the patent at issue is embodied—whether it lies in a change of system architecture, or in changes of technical scenarios or user applications;

Step 2: Determining the relationship between the technical problem solved by the distinguishing features and the intergenerational change—namely, whether the problem is a new problem introduced by the intergenerational change, or whether it is a traditional problem that has long existed in the development of communication technologies; and

Step 3: Making an overall assessment of whether the prior art provides any technical motivation, by standing in the position of a person skilled in the art, grasping the entire inventive concept, and at the same time paying attention to the technical field, technical problem, technical means, and technical effect.

EIP Thoughts

This case highlights the complexity of assessing inventive step in rapidly evolving industries like telecommunications. When standards evolve from one generation to another, the legal question is not simply whether features are known, but whether there is a real technical motivation to combine them across different contexts.

Key takeaways include:

1. Standard evolution matters: Moving from 4G to 4.5G did not merely extend existing techniques; it introduced new technical problems (e.g., inter-band configuration mismatches).
2. Problem-solution analysis is central: The invention’s distinguishing feature addressed a problem that did not exist in the 4G scenario.
3. Combination obstacles: Even if individual features are known, if the prior art operates in different technical contexts, there may be no reasonable teaching or motivation to combine them.
4. Strategic implications: For companies in standard-driven fields, careful patent drafting to emphasize “new scenario” problems and technical effects can make patents more robust in invalidation proceedings.

For patent applicants and owners, especially outside the telecom sector, this case offers broader lessons:

1. Highlight the “new scenario”: When drafting applications, clearly explain how the invention addresses problems unique to the next generation of technology.
2. Differentiate timing and context: Small distinctions, such as when feedback is determined (at configuration vs. during operation), can carry significant weight in validity disputes.
3. Anticipate standard evolution: Patents that bridge multiple generations of standards often become central to licensing negotiations and litigation.
4. Global litigation dynamics: Standard-essential patents (SEPs) frequently trigger parallel disputes across jurisdictions; consistent claim drafting and prosecution strategies are crucial.

The “Carrier Aggregation Feedback” case is a textbook example of how technical innovation, standard evolution, and global patent litigation intersect. For industries where standards evolve quickly—telecommunications, computer networking, and beyond—patent protection strategies should not only focus on current implementations but also anticipate how future standards may reshape technical problems and solutions.

If you would like to have more information on this matter or would like to have our advice, please feel free to contact us at [email protected].

This article is for general informational purposes only and should not be considered legal advice or a legal opinion on a specific set of facts.

1. “Case Five: Invalidation Request for the Invention Patent ‘Carrier Aggregation Feedback Method, Device, and System’ 案例五：“载波聚合反馈方法、装置及系统”发明专利权无效宣告请求,” https://www.cnipa.gov.cn/art/2025/6/6/art_2648_200008.html, published on June 6, 2025, accessed on September 5, 2025.

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2. Patent No.: ZL201210137097.1

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3. Datang Mobile Communications Equipment Co., Ltd.

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4. Samsung (China) Investment Co., Ltd.

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5. “Case Five: Invalidation Request for the Invention Patent ‘Carrier Aggregation Feedback Method, Device, and System’ 案例五：“载波聚合反馈方法、装置及系统”发明专利权无效宣告请求,” https://www.cnipa.gov.cn/art/2025/6/6/art_2648_200008.html, published on June 6, 2025, accessed on September 5, 2025.

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