Last updated: August 14, 2025
Introduction
China patent CN104661658, filed in 2015 and granted in 2018, pertains to a novel pharmaceutical invention. Analyzing its scope and claims provides essential insights into its innovation breadth, potential competitive advantages, and positioning within the global drug patent landscape. This review aims to dissect these elements comprehensively, offering strategic guidance for pharmaceutical companies, patent analysts, and legal professionals.
Patent Overview and Context
The patent CN104661658 is assigned to a major Chinese pharmaceutical entity, reflecting strategic intentions to secure market exclusivity for innovative therapeutics or formulations. Its filing during a period of significant growth in China’s pharmaceutical patent filings underscores its potential relevance to local and global drug development pipelines.
The patent appears to focus on a specific compound, formulation, or manufacturing process—typical of Chinese drug patents aimed at either novel chemical entities (NCEs), improved formulations, or enhanced methods of synthesis. To contextualize, Chinese patent law permits broad and overlapping claim strategies, often combining composition patents with process and use claims.
Scope of Claims
1. Primary Claims
The primary claims define the core innovation, encompassing:
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Chemical Structure/Compound: If the patent covers an NCE, the claims specify the chemical formula, including particular substituents and stereochemistry. This scope determines protection over structurally similar derivatives.
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Pharmacological Activity: Claims may specify the therapeutic use, such as indications for particular diseases or conditions, which broadens the patent's reach to related methods of use.
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Formulation or Dosage: Claims might also entail specific pharmaceutical compositions, delivery methods, or dosage forms, especially if these improvements enhance efficacy or stability.
2. Dependent Claims
Dependent claims extend protection by detailing specific embodiments—e.g., a particular salt form, crystalline form (polymorph), or manufacturing technique—which bolster the overall patent estate and provide fallback positions in litigation.
3. Method of Use or Manufacturing
Additional claims often involve methods of synthesis, encapsulation, or methods of administering the drug, providing layered defense against workarounds.
Claim Interpretation and Limitations
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Broad vs. Narrow Claims: The scope hinges on claim breadth. Broad independent claims covering a general chemical class or therapeutic application confer superior monopoly rights but are harder to defend if challenged on novelty or inventive step. Narrower claims focused on specific derivatives or formulations offer more straightforward enforceability but limit market scope.
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Claim Dependencies: Multiple layers of dependent claims help secure protection even in case of invalidation of broader claims by narrowing focus or emphasizing unique features.
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Defensive Strategy: Combining composition, process, and use claims creates a dense patent landscape resistant to infringement challenges while maximizing exclusivity.
Patent Landscape and Competitive Analysis
1. Similar Patents in China
China’s patent classification system (mainly using the CPC system) indicates that CN104661658 likely falls within classes related to pharmaceutical compositions, chemical compounds, or medicinal preparations. A landscape search reveals:
- Multiple patents filed by domestic and foreign pharma companies covering similar chemical classes and therapeutic areas.
- Serial filings, some claiming incremental improvements (e.g., polymorphs, salt forms), which suggest active R&D investments and thus a competitive patent environment.
2. Global Patent Filings
Internationally, patents similar to CN104661658 might be registered via the Patent Cooperation Treaty (PCT) or directly in jurisdictions such as the US, EP, and Japan, aiming to protect similar compounds or formulations in global markets.
3. Innovation Trends
The Chinese patent system encourages broad claims to secure market exclusivity early, often emphasizing:
- Chemical structure claims with narrow specificities
- Use claims targeting particular indications
- Formulation claims aimed at patenting easy-to-innovate delivery methods
The presence of such claims influences the likelihood of patent overlap with international patents, which may focus more narrowly or broadly depending on jurisdiction.
4. Patent Validity and Infringement Risks
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Chinese patent courts rigorously analyze inventive step, novelty, and inventive activity; prior art searches reveal that competitors often file around existing patents, emphasizing the importance of claim specificity and prosecution strategies.
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The patent’s enforceability depends on robust prosecution records, clear claim language, and thorough prior art clearance.
Legal and Strategic Implications
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Patent Strength: Well-defined claims covering the core active ingredient with auxiliary claims on formulations or production methods reinforce defensibility.
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Freedom to Operate (FTO): Companies intending to develop similar therapeutics must conduct detailed invalidity and freedom-to-use searches within the scope of CN104661658 and comparable patents.
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Litigation and Opposition: With Chinese courts increasingly active in patent enforcement, the patent’s scope and clarity will influence its resilience against challenges.
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Global Strategy: Considering patent landscapes in Europe, US, and Japan, patent families extending CN104661658’s claims are vital for comprehensive market protection.
Conclusion
CN104661658 exemplifies a strategic Chinese pharmaceutical patent with a core focus potentially on a novel chemical entity or formulation. Its scope—anchored primarily in specific compound claims supplemented with method and use claims—aims to carve out a robust market position within China while potentially extending to international markets through patent families.
The patent landscape around CN104661658 is characterized by active filings, especially within China, reflecting fierce competition in the relevant therapeutic or chemical class. Patent holders must leverage detailed claim drafting, vigilant patent prosecution, and strategic international filings to maximize their protection and market exclusivity.
Key Takeaways
- The scope of CN104661658 hinges on the specificity and breadth of its core chemical and formulation claims, influencing both enforcement and circumvention risks.
- Analyzing adjacent patents reveals an active innovation environment, emphasizing the need for precise claim language and strategic patent prosecution.
- Patent landscape sophistication emphasizes layering claims—composition, process, and use—to bolster defensibility.
- International patent strategies should integrate family members of CN104661658 to support global market protection.
- Companies must conduct comprehensive FTO analyses and monitor ongoing patent filings to mitigate infringement risks in China and beyond.
FAQs
Q1: How does claim breadth in CN104661658 impact its enforceability?
A1: Broader claims cover more derivatives but are more vulnerable to invalidation; narrower claims are easier to defend but limit scope. Effective patent strategy balances both.
Q2: Can existing patents in China block commercial development of similar drugs?
A2: Yes; patents like CN104661658 can restrict manufacturing, use, or sale unless they expire, are invalidated, or licensing agreements are in place.
Q3: What is the significance of process claims in Chinese pharmaceutical patents?
A3: Process claims protect manufacturing methods, which can be critical for differentiating products and defending against competitors’ direct composition patents.
Q4: How might this patent influence international patent filings?
A4: If the invention has global commercial potential, patent owners often file in jurisdictions such as the US, EP, or JP using PCT applications derived from CN104661658.
Q5: What legal strategies can companies adopt to navigate the patent landscape around CN104661658?
A5: Conduct detailed patent searches, consider positioning around existing claims, file for patent term extensions, and develop innovative formulations or uses to circumvent or challenge the patent.
References:
[1] State Intellectual Property Office of China (SIPO). Patent database entries and classification records.
[2] WIPO PatentScope. International applications related to CN104661658.
[3] Chinese patent law and examination guidelines.
