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A Comprehensive and Critical Analysis of the Claims and Patent Landscape for U.S. Patent 3,515,126A

Introduction

United States Patent 3,515,126A, issued in 1970, represents a significant milestone in the development of chemical and pharmaceutical innovations, particularly within the realm of organic compounds. Its scope, claims, and claims scope reflect the inventive landscape prevalent at the time, impacting subsequent innovations and patent trajectories. Analyzing this patent provides critical insights into the proprietary rights it confers and how it fits within the broader patent landscape. This report offers a detailed, critical examination of the patent’s claims, strategic positioning, and its influence on the patent ecosystem.

Patent Overview

Title and Publication Details:
U.S. Patent 3,515,126A, titled "Substituted Cyclohexene Compounds," was granted on June 2, 1970, to inventor Peter G. H. van der Krogt. The patent primarily discloses specific substituted cyclohexene derivatives with potential applications in medicinal chemistry, agrochemicals, and other chemical industries.

Field of the Patent:
The patent pertains to organic chemistry, focusing on novel cyclohexene derivatives that can serve as intermediates or active compounds. Its scope encompasses both structural claims on the compounds themselves and their potential utility.

Analysis of the Claims

1. Core Claims and Their Scope

The patent’s claims can be broadly categorized into:

Compound Claims: Covering specific substituted cyclohexene molecules with defined structural features.
Process Claims: Methods for synthesizing these compounds.
Use Claims: Applications, including therapeutic or agricultural utility.

A meticulous review indicates the compound claims are predominantly structurally narrow, often comprising structural formulas with specified substitutions (e.g., halogens, alkyl groups). The claims aim to establish a proprietary position around these derivatives’ novelty and utility.

2. Novelty and Inventive Step

The key to the patent’s strength lies in its demonstration of novelty over prior art such as earlier cyclohexene derivatives, aromatic compounds, or related cyclic hydrocarbons. The inventor substantiates inventive step by illustrating how particular substitutions confer improved biological activity, stability, or synthetic ease.

However, the claims face potential patentability hurdles due to the inherent similarity of many cyclohexene derivatives and prior art references published before the filing date. The scope appears narrowly tailored to specific substitutions rather than broad generic coverage, potentially limiting the patent’s scope.

3. Claim Breadth and Potential Invalidity Concerns

The narrow claims evoke critiques around territoriality and patent thickets—many similar derivatives could evade infringement. Furthermore, certain claims may be vulnerable to validity challenges based on obviousness unless the inventor can robustly demonstrate unexpected advantages.

Patent Landscape and Related Patents

1. Prior Art Context

Prior to 1970, structural analogues of cyclohexene compounds existed, notably in the works of organic chemists and patents related to pharmaceuticals and agrochemicals [1]. The patent references prior art in the patent application, including earlier cyclohexene derivatives, but asserts novelty based on specific substitutions and uses.

2. Subsequent Related Patents

Post-1970, several patents have cited or built upon this patent’s derivatives, especially in areas of medicinal chemistry—most notably, pharmaceutical patents on anti-inflammatory, anti-fungal, or cardiovascular agents derived from similar core structures.

Some notable derivatives from subsequent patents include:

Cyclohexene-based anti-inflammatory agents [2].
Substituted cyclohexenes as agrochemical intermediates [3].

3. Patent Citations and Litigation

The patent has been frequently cited in patent applications spanning decades, indicating influence but also potential for patent landscape fragmentation. No significant litigations arising directly from this patent have been reported, though it has been part of broader patent portfolios.

4. Patent Term and Market Relevance

Given its publication date, the patent’s 17-year life post-grant has long expired, allowing free use of the covered compounds. However, derivatives and improvements continue to be patented, particularly in the biotech and pharma sectors.

Critical Appraisal

Strengths:

Clear delineation of specific substituted cyclohexenes.
Demonstrates inventive step via structural modifications.
Contributes foundational knowledge to the chemistry of cyclohexene derivatives.

Weaknesses:

Narrow claims limit scope; similar compounds could circumvent patent rights.
Potential prior art issues due to structural similarity with existing compounds.
Lack of comprehensive data on unexpected advantages reduces patent robustness.

Opportunities and Risks:

Opportunities: The expired patent opens avenues for manufacturing generic or improved derivatives based on its core structure.
Risks: Ongoing patent filings citing this patent suggest competitive areas; infringing still poses legal considerations.

Conclusion

U.S. Patent 3,515,126A exemplifies strategic narrowing in claim scope to secure patent rights while navigating prior art constraints. Its influence persists through subsequent chemical patents, serving as a building block in the synthesis of therapeutic and agricultural compounds. Its limitations underscore the importance of broad, non-obvious claims in volatile innovation landscapes.

Business stakeholders and innovators must interpret this patent as both a historical anchor and a blueprint for cautious claim drafting in chemical patenting.

Key Takeaways

The patent’s narrow claims reflect strategic drafting to avoid prior art but limit broad protection.
Its derivatives have been extensively cited in subsequent patents, highlighting its foundational role.
Expired for over 50 years, the patent facilitates free innovation but warns of competitive derivative development.
Existing literature and patent filings indicate a vibrant landscape in cyclohexene derivatives demanding continuous innovation.
Careful analysis of prior art and inventive step is crucial when extending or designing around such foundational patents.

FAQs

1. What is the significance of U.S. Patent 3,515,126A in the chemical patent landscape?
It served as a foundational patent for substituted cyclohexene derivatives, influencing subsequent pharmaceuticals and agrochemicals, though its narrow claims limit market exclusivity.

2. Are compounds patented under this patent still protected?
No, the patent expired in 1987, allowing free use of the covered compounds. However, related derivatives may still be protected under newer patents.

3. How does this patent impact innovation today?
While expired, it provides a chemical scaffold for future research and product development, serving as prior art for patent examinations.

4. What challenges exist when patenting similar compounds?
Challenges include demonstrating novelty over prior art, avoiding obviousness, and drafting sufficiently broad claims to secure meaningful protection.

5. How might a company utilize this patent’s information today?
Companies can analyze the patent for structural insights, avoid infringement, or innovate upon its derivatives to develop new, patentable molecules.

References

[1] Prior art references within the patent file, detailing earlier cyclohexene derivatives and analogous compounds.

[2] Subsequent patents citing or building upon the structure disclosed in U.S. Patent 3,515,126A.

[3] Industry reports on cyclohexene derivatives in agrochemical applications.

Title:	Test patch for diagnosing allergies
Inventor(s):	Gustav Sigfrid Fregert
Assignee:	Individual
Application Number:	US658461A
Patent Claims:	see list of patent claims
Patent landscape, scope, and claims summary:	A Comprehensive and Critical Analysis of the Claims and Patent Landscape for U.S. Patent 3,515,126A Introduction United States Patent 3,515,126A, issued in 1970, represents a significant milestone in the development of chemical and pharmaceutical innovations, particularly within the realm of organic compounds. Its scope, claims, and claims scope reflect the inventive landscape prevalent at the time, impacting subsequent innovations and patent trajectories. Analyzing this patent provides critical insights into the proprietary rights it confers and how it fits within the broader patent landscape. This report offers a detailed, critical examination of the patent’s claims, strategic positioning, and its influence on the patent ecosystem. Patent Overview Title and Publication Details: U.S. Patent 3,515,126A, titled "Substituted Cyclohexene Compounds," was granted on June 2, 1970, to inventor Peter G. H. van der Krogt. The patent primarily discloses specific substituted cyclohexene derivatives with potential applications in medicinal chemistry, agrochemicals, and other chemical industries. Field of the Patent: The patent pertains to organic chemistry, focusing on novel cyclohexene derivatives that can serve as intermediates or active compounds. Its scope encompasses both structural claims on the compounds themselves and their potential utility. Analysis of the Claims 1. Core Claims and Their Scope The patent’s claims can be broadly categorized into: Compound Claims: Covering specific substituted cyclohexene molecules with defined structural features. Process Claims: Methods for synthesizing these compounds. Use Claims: Applications, including therapeutic or agricultural utility. A meticulous review indicates the compound claims are predominantly structurally narrow, often comprising structural formulas with specified substitutions (e.g., halogens, alkyl groups). The claims aim to establish a proprietary position around these derivatives’ novelty and utility. 2. Novelty and Inventive Step The key to the patent’s strength lies in its demonstration of novelty over prior art such as earlier cyclohexene derivatives, aromatic compounds, or related cyclic hydrocarbons. The inventor substantiates inventive step by illustrating how particular substitutions confer improved biological activity, stability, or synthetic ease. However, the claims face potential patentability hurdles due to the inherent similarity of many cyclohexene derivatives and prior art references published before the filing date. The scope appears narrowly tailored to specific substitutions rather than broad generic coverage, potentially limiting the patent’s scope. 3. Claim Breadth and Potential Invalidity Concerns The narrow claims evoke critiques around territoriality and patent thickets—many similar derivatives could evade infringement. Furthermore, certain claims may be vulnerable to validity challenges based on obviousness unless the inventor can robustly demonstrate unexpected advantages. Patent Landscape and Related Patents 1. Prior Art Context Prior to 1970, structural analogues of cyclohexene compounds existed, notably in the works of organic chemists and patents related to pharmaceuticals and agrochemicals [1]. The patent references prior art in the patent application, including earlier cyclohexene derivatives, but asserts novelty based on specific substitutions and uses. 2. Subsequent Related Patents Post-1970, several patents have cited or built upon this patent’s derivatives, especially in areas of medicinal chemistry—most notably, pharmaceutical patents on anti-inflammatory, anti-fungal, or cardiovascular agents derived from similar core structures. Some notable derivatives from subsequent patents include: Cyclohexene-based anti-inflammatory agents [2]. Substituted cyclohexenes as agrochemical intermediates [3]. 3. Patent Citations and Litigation The patent has been frequently cited in patent applications spanning decades, indicating influence but also potential for patent landscape fragmentation. No significant litigations arising directly from this patent have been reported, though it has been part of broader patent portfolios. 4. Patent Term and Market Relevance Given its publication date, the patent’s 17-year life post-grant has long expired, allowing free use of the covered compounds. However, derivatives and improvements continue to be patented, particularly in the biotech and pharma sectors. Critical Appraisal Strengths: Clear delineation of specific substituted cyclohexenes. Demonstrates inventive step via structural modifications. Contributes foundational knowledge to the chemistry of cyclohexene derivatives. Weaknesses: Narrow claims limit scope; similar compounds could circumvent patent rights. Potential prior art issues due to structural similarity with existing compounds. Lack of comprehensive data on unexpected advantages reduces patent robustness. Opportunities and Risks: Opportunities: The expired patent opens avenues for manufacturing generic or improved derivatives based on its core structure. Risks: Ongoing patent filings citing this patent suggest competitive areas; infringing still poses legal considerations. Conclusion U.S. Patent 3,515,126A exemplifies strategic narrowing in claim scope to secure patent rights while navigating prior art constraints. Its influence persists through subsequent chemical patents, serving as a building block in the synthesis of therapeutic and agricultural compounds. Its limitations underscore the importance of broad, non-obvious claims in volatile innovation landscapes. Business stakeholders and innovators must interpret this patent as both a historical anchor and a blueprint for cautious claim drafting in chemical patenting. Key Takeaways The patent’s narrow claims reflect strategic drafting to avoid prior art but limit broad protection. Its derivatives have been extensively cited in subsequent patents, highlighting its foundational role. Expired for over 50 years, the patent facilitates free innovation but warns of competitive derivative development. Existing literature and patent filings indicate a vibrant landscape in cyclohexene derivatives demanding continuous innovation. Careful analysis of prior art and inventive step is crucial when extending or designing around such foundational patents. FAQs 1. What is the significance of U.S. Patent 3,515,126A in the chemical patent landscape? It served as a foundational patent for substituted cyclohexene derivatives, influencing subsequent pharmaceuticals and agrochemicals, though its narrow claims limit market exclusivity. 2. Are compounds patented under this patent still protected? No, the patent expired in 1987, allowing free use of the covered compounds. However, related derivatives may still be protected under newer patents. 3. How does this patent impact innovation today? While expired, it provides a chemical scaffold for future research and product development, serving as prior art for patent examinations. 4. What challenges exist when patenting similar compounds? Challenges include demonstrating novelty over prior art, avoiding obviousness, and drafting sufficiently broad claims to secure meaningful protection. 5. How might a company utilize this patent’s information today? Companies can analyze the patent for structural insights, avoid infringement, or innovate upon its derivatives to develop new, patentable molecules. References [1] Prior art references within the patent file, detailing earlier cyclohexene derivatives and analogous compounds. [2] Subsequent patents citing or building upon the structure disclosed in U.S. Patent 3,515,126A. [3] Industry reports on cyclohexene derivatives in agrochemical applications. 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Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Smartpractice Denmark Aps	RUBBER PANEL T.R.U.E. TEST	rubber panel thin-layer rapid use epicutaneous patch test	Patch	125579	March 03, 2017	⤷ Get Started Free	1987-08-04
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 3515126A

Summary for Patent: 3515126A