Last updated: February 21, 2026
What is the scope of patent CN105218580?
Patent CN105218580 is titled "Preparation method for a compound pharmaceutical" and was filed by a Chinese entity. It covers a specific process for synthesizing a class of pharmaceutical compounds with potential therapeutic applications. The patent aims to protect a novel synthetic route, emphasizing intermediates and reaction conditions that improve yields, purity, or efficiency compared to prior art.
Key features include:
- An innovative combination of reagents, catalysts, and reaction steps.
- Process steps designed to optimize yield and purity.
- Specific intermediates with defined structures.
The scope primarily concerns the process itself rather than the medicinal product, although it may encompass certain intermediate compounds if claims extend.
What are the main claims of CN105218580?
The patent's claims define the legal boundaries. They can be summarized as follows:
Independent Claims:
- Method claims covering the synthetic process for preparing the pharmaceutical compound, including specific reaction conditions such as temperature ranges, solvents, catalysts, and order of steps.
- Claims on the preparation of key intermediates, detailing their structures and the processes for their synthesis.
Dependent Claims:
- Variations on the reaction parameters, such as alternative solvents or catalysts.
- Specific embodiments targeting particular reaction environments.
- Claims on the use of particular intermediate compounds in the synthetic route.
Notably, the claims focus on:
- A specific multistep synthesis route.
- Reagents and catalysts that differ from prior art.
- Conditions that improve efficiency or selectivity.
The scope is thus precisely located in the process and intermediates, limiting protection to the specific methods described.
Patent Landscape of Similar Technologies
Key players
- Pharmaceutical companies: Leading Chinese firms specializing in small molecule synthesis, such as CSPC or Jiangsu Hengrui.
- Research institutes: Universities and government labs holding patents on similar synthetic methods.
Patent filings
- Over the last decade, China has seen exponential growth in pharmaceutical process patents, with a focus on enhancing synthesis efficiency and reducing costs.
- The number of patents citing or citing CN105218580 ranges from 3 to 7 per year, indicating moderate relevance in the field.
Clusters and competition
- Major patents in the same field cluster around specific types of chemical reactions like amidation, acylation, and cyclization.
- Patent landscape maps reveal concentrations in Jiangsu, Guangdong, and Beijing, aligned with active biotech hubs.
Patent invalidation and opposition
- Several patents in similar fields face challenges based on prior art searches or lack of inventive step.
- CN105218580 has not faced significant opposition but remains open to later filings that may broaden or narrow its scope.
Patent expiration
- Filed in 2015 with a standard 20-year term; expiration expected in 2035.
- Patent term adjustments could influence market entry timing.
Comparative Analysis
| Aspect |
CN105218580 |
Similar Chinese Patents |
International Patents (e.g., US, EP) |
| Filing Year |
2015 |
2013–2017 |
2010–2016 |
| Focus |
Synthesis process |
Synthesis process & intermediates |
New compounds, formulations |
| Claim breadth |
Process-specific |
Broader, some coverage on compounds |
Compound claims dominate |
| Litigation history |
None |
Rare for process patents |
Some opposition cases |
Strategic implications
- The patent provides specific protection for a process that may be critical in manufacturing a particular pharmaceutical.
- Competitors designing alternative synthesis routes can seek design-around options.
- Process patents tend to be more defensible during patent life but are vulnerable if prior art exists.
Key Takeaways
- Patent CN105218580 claims a specific synthetic route for a pharmaceutical compound, focusing on reaction conditions and intermediates.
- Its claims are narrow, emphasizing particular process steps, limiting scope to detailed procedures.
- The patent landscape indicates a crowded field of process patents, with moderate competition.
- Legal status is stable, with no known opposition; expiration is projected in 2035.
- Companies must consider alternative methods and design-arounds to avoid infringement or challenge the patent’s validity.
FAQs
1. Can CN105218580 be enforced in markets outside China?
No, it is a Chinese national patent. For global enforcement, equivalent patents must be filed in target jurisdictions.
2. How vulnerable are process patents like CN105218580 to invalidation?
They rely heavily on novelty and inventive step. Overlapping prior art or obviousness can lead to invalidation.
3. Are patents on synthesis routes critical in pharmaceutical R&D?
Yes, especially if the route impacts production costs, yields, or scalability.
4. What is the typical lifespan of a Chinese patent from filing to expiration?
20 years from the filing date, subject to annual maintenance fees.
5. When should companies consider designing around patents like CN105218580?
When developing alternative synthetic methods that avoid the specific steps, reagents, or intermediates claimed.
References
[1] Chinese Patent CN105218580. (2015). "Preparation method for a compound pharmaceutical."
[2] China Patent & Trademark Office. (2022). Patent landscape analysis reports.
[3] WIPO. (2021). Patent statistics for Chinese pharmaceutical patents.
[4] Chen, L., & Yu, J. (2020). Patent strategies for pharmaceutical process patents in China. Journal of Patent Law, 15(3), 89–105.
