Beyond the Basics: What Are the Key Patentability Hurdles (Novelty, Inventive Step) in Japan?

So, you've developed what you believe is a groundbreaking technology and have confirmed it meets the foundational criteria of a statutory "invention" under Japanese patent law. What's next? Before a patent is granted in Japan, your invention must clear several additional significant hurdles, primarily demonstrating both novelty and inventive step. These two requirements are central to the patent examination process and determine whether your invention truly represents a patentable contribution to the existing state of technology.

This article provides an in-depth look at these crucial patentability requirements in Japan.

I. Novelty (新規性 - Shinkisei): Is Your Invention New?

Novelty is a fundamental prerequisite for patentability worldwide, and Japan is no exception. At its core, the novelty requirement ensures that patents are not granted for inventions that are already part of the public domain.

A. The Fundamental Principle and Rationale

Article 29(1) of the Japanese Patent Act lays down the novelty requirement. The rationale behind this is twofold:

1. No Need for Incentives for Known Technology: The patent system aims to incentivize the creation and disclosure of new technologies. If an invention is already known or available to the public, there is no societal benefit in granting an exclusive right to it, as the incentive for its creation or disclosure is no longer relevant.
2. Avoiding Detriment to the Public: Granting a monopoly on existing technology would unjustly restrict the public's freedom to use what is already known and could disrupt ongoing activities based on that knowledge.

Essentially, an invention must be new to the world, not just new to the inventor, to be eligible for a patent.

B. The Critical Date and Scope for Assessing Novelty

• Critical Time: Novelty is assessed as of the filing date of the patent application in Japan. This emphasizes the importance of filing an application promptly after an invention is made. If priority is claimed from an earlier foreign application under the Paris Convention, the novelty (and inventive step) is generally assessed based on the prior art existing at the time of that priority date.
• Territorial Scope: Japan employs a global novelty standard. This means an invention is not considered novel if it was publicly known, publicly worked, or described in a publication anywhere in the world before the filing date. This worldwide standard replaced a more limited domestic scope in a 1999 amendment, reflecting the increasing globalization of information.

C. What Destroys Novelty? Statutory Bars under Article 29(1)

Article 29(1) of the Patent Act specifies three main categories of disclosures that can destroy the novelty of an invention if they occurred before the filing date:

1. Publicly Known Inventions (公然知られた発明 - Kōchi Hatsumei) (Article 29(1)(i))
   This refers to an invention that was publicly known in Japan or a foreign country before the filing of the patent application.
   • "Publicly known" means the content of the invention became accessible to an unspecified number of people, without any obligation of confidentiality. The number of people who actually knew the invention is not the determining factor; the possibility of access by the public is key.
   • Examples include disclosures through lectures, oral presentations at conferences open to the public, or public demonstrations where the invention's details could be understood, unless clear confidentiality measures were in place. Disclosure to individuals under a specific obligation of secrecy (e.g., via a non-disclosure agreement) generally does not constitute public knowledge.
2. Publicly Worked Inventions (公然実施された発明 - Kōyō Hatsumei) (Article 29(1)(ii))
   This covers an invention that was publicly worked (e.g., used, manufactured, sold) in Japan or a foreign country before the patent application was filed.
   • "Publicly worked" means the invention was put into practice in a way that its content could be understood by the public. It is not necessary that the public actually understood the invention, only that they had the opportunity to do so.
   • This can include the sale of a product embodying the invention if the invention can be understood from the product itself, perhaps through analysis or reverse engineering. However, if the invention is, for example, an internal manufacturing process that cannot be discerned from the final product sold, then selling the product might not necessarily constitute public working of the process invention itself.
3. Inventions Described in Distributed Publications or Made Publicly Available via Telecommunication Lines (文献公知発明 - Bunken Kōchi Hatsumei) (Article 29(1)(iii))
   This category includes inventions that were described in a publication distributed in Japan or a foreign country, or made available to the public through electric telecommunication lines (such as the internet), before the filing of the patent application.
   • A "publication" is broadly interpreted to include any information carrier duplicated for public disclosure, such as patent documents, academic journals, books, technical manuals, and even CD-ROMs. The key is that it was "distributed," meaning made available for public inspection, not necessarily that someone actually read it. The Second Box Rule Case (Supreme Court, July 17, 1986, a utility model case decided before the 1999 amendment) held that microfilms available only within a foreign patent office could still be considered distributed publications.
   • "Made publicly available via telecommunication lines" explicitly covers disclosures on the internet. The information must have been accessible to an unspecified number of people; actual access by a user is not required. Even if a password or payment was needed, if access was generally available to the public, it could be novelty-destroying. The evidentiary challenges of proving the content and date of online disclosures are, of course, a practical consideration.

The prior art disclosed in these ways is often referred to as "cited inventions" (引用発明 - in'yō hatsumei) during examination.

D. Anticipation: The Standard of Identity

For a prior art disclosure to destroy the novelty of a claimed invention (i.e., to anticipate the invention), the disclosure must generally describe the invention in such a way that a person skilled in the art would have been able to understand and practice the claimed invention based on that disclosure. The prior art reference must contain all the essential features of the claimed invention. If the prior art reference only discloses some elements, or a broader concept that does not specifically point to the claimed invention, novelty might still be intact, though inventive step could be an issue.

E. Special Considerations and Exceptions Affecting Novelty

1. Grace Period for Loss of Novelty (新規性喪失の例外 - Shinkisei Sōshitsu no Reigai) (Article 30)
   Japanese patent law provides a crucial "grace period" that can, under certain circumstances, allow an inventor to file a patent application even after making a public disclosure of their invention, without that disclosure destroying novelty. This is a vital provision, especially for academics and researchers who may need to publish or present their findings.
   • Disclosures by the Right Holder: If the person having the right to obtain a patent (inventor or their assignee) discloses the invention (e.g., through a scientific publication, presentation at a conference, exhibition, or online disclosure), they can still file a patent application in Japan within one year from the date of such disclosure and claim the benefit of the grace period. This one-year period is an update from the six-month period mentioned in the 2014 document and was part of amendments aligning with international practices.
   • Disclosures Against the Will of the Right Holder: If the invention was disclosed against the will of the right holder (e.g., through industrial espionage), they can also benefit from the grace period if they file within one year of the disclosure.
   • Procedure: To claim the grace period, the applicant must typically file a statement to that effect at the time of filing the patent application and subsequently submit documents proving the facts of the disclosure.
   • Limitations: It's important to note that the grace period only protects against the applicant's own (or against-their-will) prior disclosures. It does not protect against independent disclosures made by third parties before the application filing date.
2. Prior Art Effect of Earlier-Filed, Later-Published Applications (拡大先願 - Kakudai Sengan) (Article 29-2)
   This is a unique provision in Japanese patent law that can affect novelty. Even if an earlier patent application filed by another party was not published until after your own patent application was filed, an invention described in the specification or drawings of that earlier application can still destroy the novelty of an identical invention claimed in your application, provided the earlier application is eventually published.
   • Rationale: This rule aims to prevent double patenting for the same invention and to give some prior art effect to the entire content of earlier applications once they are laid open, not just to their claims as of their filing date under the first-to-file principle (Article 39). It also helps prevent applicants from obtaining patents for inventions that were, in substance, already disclosed to the JPO by another party, even if not yet publicly available at the time of the later filing.
   • Exceptions: Article 29-2 does not apply if, at the time of your filing, the inventor or the applicant of the earlier application is the same as for your application.

II. Inventive Step (進歩性 - Shinposei): Is Your Invention Non-Obvious?

Even if an invention is proven to be novel (i.e., not identically disclosed in the prior art), it must also possess an "inventive step" to be patentable. This is stipulated in Article 29(2) of the Japanese Patent Act.

A. The Core Concept (Article 29(2))

An invention is considered to lack inventive step if a person ordinarily skilled in the art to which the invention pertains (often abbreviated as PSA or PHOSITA) could have easily arrived at the invention based on the publicly known art (as defined under Article 29(1)(i)-(iii)) available before the filing date of the patent application. This concept is broadly analogous to the "non-obviousness" requirement under U.S. patent law or the "inventive step" requirement in European patent law.

B. Rationale for the Inventive Step Requirement

The requirement for an inventive step serves several purposes:

• Preventing Patents for Trivial Modifications: It ensures that patents are not granted for minor or obvious modifications, routine developments, or simple combinations of known technologies that do not represent a genuine inventive contribution.
• Ensuring a Substantial Contribution: Patents grant significant exclusive rights. The inventive step requirement aims to ensure that such rights are reserved for inventions that provide a substantial enough technological advancement beyond what was already known or easily achievable.
• Balancing Monopoly Costs and Benefits: One perspective offered suggests that the inventive step requirement helps to filter out inventions where the societal cost of granting a monopoly (e.g., higher prices, restricted access) would outweigh the benefit of incentivizing their (perhaps only slightly earlier) creation. Inventions that would naturally emerge in due course through routine engineering or development by those skilled in the art may not warrant the societal burden of a patent monopoly.

C. The "Person Skilled in the Art" (当業者 - Tōgyōsha)

The assessment of inventive step is made from the perspective of this hypothetical "person skilled in the art".

• Definition: This is not a specific individual but an abstract legal construct representing a person with ordinary knowledge and skills in the particular technical field of the invention as of the filing date. They are presumed to have access to all relevant prior art.
• Level of Skill: The perceived level of skill of the PSA can significantly influence the inventive step assessment. If the PSA is deemed highly skilled, more variations might be considered "easily arrived at." The definition of the relevant technical field is also crucial; a narrowly defined field might imply a more specialized PSA, while a broader definition might imply a PSA with more general knowledge.
• Distinction from PSA for Enablement: The text notes that the PSA for assessing inventive step (who is involved in the creative act of invention) might be considered to have a somewhat different, perhaps more innovative, skill set than the PSA for assessing enablement of disclosure (who needs to be able to understand and work the invention).

D. The Assessment Process

The JPO's Examination Guidelines outline a general approach to assessing inventive step, which typically involves:

1. Determining the Claimed Invention: Understanding the scope and features of the invention as defined in the patent claims.
2. Identifying the Closest Prior Art: Searching for and selecting the most relevant prior art reference(s).
3. Analyzing the Differences: Comparing the claimed invention with the closest prior art to identify the distinguishing features.
4. Evaluating "Ease of Arrival": Considering whether a PSA, faced with the technical problem addressed by the invention and knowing the prior art, could have easily arrived at the claimed distinguishing features by, for example, combining or modifying known prior art, or applying common general knowledge.

Examiners often look for a "motivation" or "suggestion" in the prior art that would have led the PSA to make the necessary modifications or combinations to arrive at the claimed invention. The absence of such motivation can be an argument for inventive step.

E. Factors Indicating Inventive Step (Secondary Considerations)

While the primary test revolves around the ease of arrival from the prior art, certain objective factors, sometimes called "secondary considerations" (though not always formally termed as such in Japan), can provide evidence supporting the presence of an inventive step:

• Unexpected or Remarkable Effects (顕著な効果 - Kencho na Kōka): If the invention achieves an effect that is surprisingly superior to, or qualitatively different from, what would have been expected from the prior art, this can be a strong indicator of inventive step. This is often relevant for selection inventions, use inventions, or inventions involving specific numerical limitations that lead to unforeseen advantages.
• Overcoming a Long-Felt Need: If the invention solves a technical problem that the industry has been trying to overcome for a long time without success.
• Overcoming Technical Prejudice: If the invention succeeds by going against established technical beliefs or teachings in the field.
• Commercial Success (with a clear nexus to the invention's technical features): While the JPO and courts tend to be cautious about relying heavily on commercial success (as it can be due to factors other than technical merit, like marketing), significant commercial success that is demonstrably linked to the technical advantages of the invention can sometimes be considered as supporting evidence.

F. Common Reasons for Lacking Inventive Step

Conversely, inventive step is often found lacking in situations such as:

• Mere aggregation of known elements or features where each element performs its known function without any new, unexpected synergistic effect.
• Obvious selection of optimal materials, dimensions, or operating conditions from a known range where the outcome is predictable.
• Simple substitution of a known element with a well-known equivalent.
• Obvious application of a known technique to an analogous field or purpose.
• Routine design modifications or workshop improvements.

G. Grace Period and Inventive Step

As with novelty, disclosures that qualify for the grace period under Article 30 generally do not form a basis for an inventive step objection if the patent application is filed within the prescribed grace period. The disclosure itself is, in effect, disregarded for the purpose of assessing inventive step against the applicant's own work.

III. Interrelation Between Novelty and Inventive Step

Novelty and inventive step are distinct but hierarchically related requirements.

• An invention that lacks novelty (i.e., is identical to a prior art disclosure) will inherently lack inventive step. If it's already known, it cannot be non-obvious.
• However, the converse is not true. An invention can be novel (i.e., not identically disclosed in the prior art) but still lack inventive step if the differences between the invention and the prior art are such that a PSA could have easily bridged them.

From a procedural standpoint, novelty is often easier for examiners to assess because it involves a more direct comparison for identity. Inventive step involves a more complex, evaluative judgment about what a PSA would have found "easy" or "obvious." Therefore, if an invention is clearly anticipated by a single prior art reference, an examiner might reject it for lack of novelty without needing to undertake a full inventive step analysis.

Conclusion

Navigating the patentability landscape in Japan requires a clear understanding that an "invention" must not only be new (novelty) but also represent a non-obvious advancement over existing technology (inventive step). For businesses, this means that before investing in a Japanese patent application, a thorough prior art search and a critical assessment of both novelty and inventive step from the perspective of a person skilled in the relevant Japanese technical field are indispensable. The availability of a grace period offers some flexibility for prior disclosures, but its conditions must be carefully met. Ultimately, successfully overcoming these key patentability hurdles is paramount to securing robust and enforceable patent rights in Japan.