Genus vs. Species: Patentability Assessment Strategy
Pine IP
October 29, 2024
To register a new invention as a patent, it must satisfy the requirements of novelty, inventive step (non-obviousness), and industrial applicability. Within this process, the way the scope of the invention is defined and articulated critically impacts the assessment of patentability, particularly concerning novelty and inventive step. Specifically, the relationship between broad-scope genus inventions and the specific species inventions falling within them raises crucial and complex issues in patent examination and litigation practice.
In this column, Pine IP Firm clearly defines genus and species inventions, provides an in-depth analysis of how patentability (especially novelty and inventive step) is assessed in each scenario, and explores practical strategies for applicants and rights holders to consider.
1. Definitions of Genus and Species
Genus: A broad concept encompassing an entire group sharing common properties or structures. Examples include 'alkyl group,' 'halogen element,' 'metal oxide,' or 'a group of compounds satisfying a specific structural formula.' This defines the invention broadly, enabling comprehensive rights protection.
Species: A specific, individual entity or example included within a genus. Examples are 'methyl group' (a species of alkyl group), 'chlorine' (a species of halogen element), 'titanium dioxide' (a species of metal oxide), or 'specific compound A within a defined group of structural formulas.'
2. When a Genus Invention Exists in Prior Art (Assessing Patentability of a Species Invention)
A common scenario involves determining whether a specific species invention, falling within the scope of a broadly disclosed genus invention in the prior art, can be patented.
Assessment of Novelty: In principle, if a genus is described in the prior art, a species within it might literally be considered 'not new.' However, case law and examination guidelines generally do not deny novelty to all species simply because the genus is disclosed. If the prior art document does not specifically recognize or exemplify the species—meaning it is not 'explicitly disclosed'—novelty may be acknowledged. Nevertheless, novelty might be denied if the scope of the genus is very narrow or if selecting that particular species is considered inevitable from the disclosure.
Assessment of Inventive Step (Non-Obviousness): Even if novelty is established, securing inventive step is the crucial challenge. If selecting a specific species from a known genus is considered obvious to a person skilled in the art (POSITA), inventive step will be denied. In such cases, the doctrine of 'Selection Invention' is often applied to determine if the species invention possesses an inventive step.
What is a Selection Invention? A selection invention is a legal principle acknowledging inventive step when a specific species is selected from a known genus, and this species exhibits effects that are qualitatively different from, or quantitatively remarkable compared to, the effects known from the prior art (genus), provided these effects were unpredictable to a POSITA based on the prior art.
Requirements:
Selection: The species must clearly fall within the scope of the disclosed genus.
Qualitative Difference or Quantitative Remarkableness of Effect: The selected species must demonstrate a special and superior effect compared to other members within the genus or the generic teaching. This requires more than a mere difference in degree; it necessitates a significant, unpredictable improvement or the emergence of a new property.
Unpredictability: This remarkable effect must not have been easily predictable by a POSITA based on the disclosure of the prior art genus invention or the state of the art at the time.
Points to Note: Merely narrowing the scope of the genus or selecting an optimal value within a known trend is generally insufficient. One must demonstrate an effect akin to an unpredictable 'technical leap' or an 'unexpected discovery.' Objectively proving the remarkableness of the effect through comparative experimental data is crucial.
3. When Species Inventions Exist in Prior Art (Assessing Patentability of a Genus Invention)
Conversely, if one or several specific species inventions are already known, can a genus invention encompassing them be patented?
Assessment of Novelty: Generally, if only one or a few species are known, the genus encompassing them is likely to be considered 'new.' This is because the prior art only disclosed specific species, not the entire genus. However, if the number of disclosed species in the prior art is very large and representative, such that it effectively discloses the entire genus, novelty might be denied.
Assessment of Inventive Step (Non-Obviousness): Even if novelty is acknowledged, establishing inventive step is very difficult. This is because generalizing common properties from known species to form a broader genus is often considered obvious to a POSITA. For instance, if known species (A, B, C) share a common structure X and exhibit a superior effect Y, claiming 'all substances with structure X (the genus)' based on the prediction that they will all have effect Y is likely to lack inventive step.
Potential Exceptions for Acknowledgment:
Synergistic or Emergent Effect: If there's a new, unpredictable technical effect that manifests only when considering the genus as a whole, and was not apparent from the individual species.
Difficulty in Generalization: If there was a technical prejudice (teaching away) against generalizing from the known species to the genus, or if significant technical hurdles prevented a POSITA from easily making the generalization.
Practical Difficulty: Securing inventive step for a genus when species exist in the prior art is significantly more challenging than for a selection invention. Simply grouping existing technologies to claim a broad scope is highly likely to be rejected for lack of inventive step.
4. Practical Considerations and Strategy
Specification Drafting:
Diverse Claims: To protect the core idea, it's advantageous to draft both broad genus claims and dependent claims (or separate independent claims) specifying important species. This provides flexibility during examination and potential future disputes.
Sufficient Examples (Embodiments): When claiming a genus, providing sufficient and diverse examples to support the breadth of the claim is crucial. For species (selection inventions), comparative data demonstrating the unpredictable, remarkable effect is essential. This is also vital for meeting description requirements (e.g., written description, enablement).
Prior Art Search: Conduct a thorough prior art search before filing to identify relevant genus and species disclosures. Based on this, formulate a patent strategy (claim scope definition, direction for proving effects, etc.).
Demonstrating Effects: When arguing for the inventive step of a species (selection invention), clearly demonstrate the remarkableness of its effect compared to the prior art (genus or other species) using objective data. When arguing for the inventive step of a genus, present compelling arguments regarding the non-obviousness of generalization or the presence of a synergistic/emergent effect.
Scope of Rights vs. Validity: Genus patents offer broad protection due to their wide scope but may carry a relatively higher risk of invalidation. Species patents (especially selection inventions meeting the requirements) have a narrower scope but can be robust means of protection if their validity is upheld. Finding the right balance depends on the nature of the invention and the business strategy.
Conclusion
Assessing the patentability of genus and species inventions goes beyond mere conceptual inclusion; it's a complex process centered on novelty, inventive step, and particularly the presence of unpredictable technical effects in relation to the prior art. To establish inventive step for a species when the genus is in the prior art, the requirements for a 'selection invention'—demonstrating an unpredictable, remarkable effect—must be met. Conversely, gaining acceptance for the inventive step of a genus when species are in the prior art is considerably harder, requiring satisfaction of stricter criteria, such as the non-obviousness of generalization.
Therefore, for successful patent acquisition and utilization, it is vital to consider this genus/species relationship from the R&D stage, clearly identifying the technology's distinctions and effects. During patent filing, strategic claim drafting based on thorough prior art analysis and securing sufficient supporting data are paramount.
Should you have further questions regarding the content of this column or require expert consultation, please do not hesitate to contact Pine IP Firm at any time.
