Protecting Software in Japan: Copyright for Computer Programs and its Unique Rules

Japanese Attorney at Law - Bengoshi L.L.

• 9 min read

In the digital economy, software is a critical asset, often representing substantial investment and innovation. Like many countries, Japan recognizes computer programs as works eligible for copyright protection. However, due to the unique characteristics of software—being both a form of literary expression (code) and a functional tool—the Japanese Copyright Act (著作権法 - Chosakuken-hō) incorporates a series of special provisions tailored specifically to computer programs (コンピュータ・プログラムの著作物 - konpyūta puroguramu no chosakubutsu). These rules address aspects from copyrightability and authorship to moral rights and specific limitations on exclusive rights, creating a distinct framework that businesses operating in or with Japan must understand.

Copyrightability of Computer Programs in Japan

Computer programs are explicitly listed as an example of a copyrighted work under Article 10, Paragraph 1, Item (ix) of the Copyright Act. The Act further defines a "program" in Article 2, Paragraph 1, Item (x)-ii as "an expression of combined instructions given to a computer so as to make it function and obtain a certain result."

  • What Qualifies as a "Program"? This definition implies that to be a "program" for the purposes of these special copyright rules, the set of instructions must be capable of directly causing a computer to function and achieve a specific outcome. Consequently, preparatory design materials like detailed flowcharts or written specifications, while potentially copyrightable as literary or graphical works in their own right, might not themselves be considered "programs" under this specific definition if they cannot directly execute on a computer. The presence of bugs in code does not typically negate its status as a "program."
  • The Idea-Expression Dichotomy in Software: A core principle of copyright—that it protects expression, not ideas—is particularly relevant for software. Article 10, Paragraph 3 specifically clarifies that copyright protection for program works does not extend to:
    • Programming languages: The languages themselves (e.g., Python, Java, C++) used to write programs.
    • Rules (規約 - kiyakus): This refers to protocols, interfaces, and other conventions necessary for interoperability between programs or systems (e.g., data formats, communication protocols).
    • Solutions (解法 - kaihō): This refers to algorithms or methods of processing information within a program—essentially, the underlying logic or problem-solving steps.

This means that while the literal source code and object code of a program are protected as expression, the underlying algorithms, programming techniques, or the functional specifications (the "ideas") are not. Japanese courts, when assessing similarity in software infringement cases, often look at the degree of literal and non-literal similarity in the code itself, sometimes considering the proportion of copied lines while filtering out unprotectable elements like algorithms or standard programming routines.

Authorship of Computer Programs: The Special Shokumu Chosaku Rule (Article 15(2))

A significant specific rule for computer programs concerns authorship in an employment context (Shokumu Chosaku, or work made in the course of duties). While the general rule for works made by employees (Article 15(1)) requires several conditions for the employer to be deemed the author (including publication under the employer's name), Article 15, Paragraph 2 carves out a special provision for computer programs:

"The authorship of a work which is a computer program and which is created by a person engaged in the business of a juridical person, etc. (hereinafter in this Article referred to as a "juridical person, etc.") on the initiative of that juridical person, etc. in the course of his duties shall be attributed to that juridical person, etc., as author, unless otherwise stipulated in any contract, work rules or any other instrument in force at the time of its creation."

The key distinction here is that the requirement of the work being made public under the employer's name is omitted for computer programs. If a program is created by an employee, on the employer's initiative, in the course of their duties, and there is no contractual stipulation to the contrary (e.g., in the employment agreement or work rules), the employer (juridical person) is automatically deemed the author.

  • Rationale: This rule aims to facilitate corporate control and exploitation of software developed in-house. Given the often collaborative, iterative, and functional nature of software development, and the substantial investment by employers, this provision simplifies rights management by attributing authorship directly to the employer by default. It also reflects the view that the individual programmer's personal "expressive" link to purely functional code might be less pronounced than in other types of creative works.
  • Implications for Moral Rights: If the employer is deemed the author under Article 15(2), the employer, as a juridical person, holds and exercises the author's moral rights associated with the program.
  • Related Documents: It's important to note that this special rule applies only to the "program" itself as defined in the Act. Ancillary documents like detailed design specifications, user manuals, or flowcharts, even if created by the same employee in the same project, would fall under the general Shokumu Chosaku rule of Article 15(1). For these non-program works, the employer would only be deemed the author if all conditions of Article 15(1) are met, including the (actual or intended) publication under the employer's name.

Moral Rights and Computer Programs: A Broad Exception to Integrity

Given the functional nature of software and the constant need for updates, bug fixes, porting to new platforms, and general maintenance, a strict application of the author's moral right of integrity (the right to prevent unwanted modifications) could severely hinder the usability and development of programs.

Article 20, Paragraph 2, Item (iii) provides a significant exception to the right of integrity specifically for computer programs:
"[The right of integrity does not apply to a] modification which is necessary for enabling a work to be used on a particular computer on which it would otherwise be unusable, or for making a work more effective for use on a computer."

This is a very broad exception. It permits:

  • Modifications necessary for compatibility or porting (e.g., adapting a program to run on a different operating system or hardware).
  • Modifications to enhance effectiveness (e.g., bug fixes, performance optimization, feature enhancements, version upgrades).

The practical effect is that for computer programs, the author's (often the employer's, if Article 15(2) applies) ability to object to modifications on the grounds of the right of integrity is substantially limited. As long as the modification serves the purpose of enabling use or making the program more effective, it is generally permissible. Legal commentary suggests that this exception is so broad that the right of integrity rarely becomes a barrier to legitimate software modification and development, unless perhaps a modification is made with clearly malicious intent (e.g., to deliberately introduce bugs or degrade performance, which wouldn't be for "effectiveness"). Some scholars have debated whether this allows modifications made for the benefit of third-party users (e.g., a company releasing an updated version to its customers), with the prevailing view being that it should, to ensure the practical utility of the exception.

Specific Limitations on Economic Rights for Program Users

Beyond the general copyright limitations, Japanese law provides specific rules concerning the exploitation of copies of computer programs by their lawful possessors.

1. Lawful Possessor's Right to Reproduce or Adapt (Article 47-3)

Article 47-3, Paragraph 1 grants the owner (所有者 - shoyūsha) of a copy of a program work the right to reproduce or adapt (including modifying) that work "to the extent deemed necessary for the purpose of exploiting that work on a computer for his own personal use."

  • Rationale: This provision allows legitimate users to perform acts that are often technically essential for using software, such as:
    • Making a backup copy for archival purposes in case the original is damaged or lost.
    • Installing the program onto a computer's hard drive (which involves reproduction).
    • Making minor modifications for personal compatibility or to fix bugs for their own use.
  • "Owner" vs. "Lawful Possessor": The text of Article 47-3 refers to the "owner" of the copy. This has led to debate as to whether it applies to mere licensees or lessees of software copies. Some legal commentary argues for a broader interpretation to include any lawful possessor with the right to use the program, to ensure practical usability in common scenarios like software leasing or use of programs on loaned hardware. However, the statutory language is specific to "owners."
  • "For His Own Personal Use": This is a crucial limitation. It does not permit making multiple copies for simultaneous use on several computers within an organization if only one copy was legitimately acquired (unless the software license itself permits this). It is about enabling the lawful owner to use their copy effectively.
  • "Necessary Extent": The reproduction or adaptation must be no more than what is necessary for the owner's own exploitation of that copy. This would typically cover installing the program, creating a backup, or applying patches.
  • Obligation Upon Ceasing Possession (Article 47-3(2)): If the owner of the original copy (under which these additional reproductions/adaptations were made) ceases to own that original copy (e.g., sells it), then any other copies made under the permission of Article 47-3(1) must generally be destroyed, unless the original was lost or destroyed through no fault of the owner (e.g., hardware failure, not theft). This is to prevent the proliferation of unauthorized copies.
  • Misuse of Permitted Copies (Article 49): If copies made under Article 47-3 are then used for purposes other than the owner's personal exploitation (e.g., distributed to others, or used to make the work publicly available), such acts can be deemed new acts of infringement (Article 49(1)(iv) and (2)(iv)).

2. Prohibition on Business Use of Infringing Software Copies (Article 113(2))

Article 113, Paragraph 2 provides a specific rule for the use of infringing software copies in a business context:
"An act of exploiting on a computer, in the course of business, a copy of a work which is a computer program made by an act infringing copyright in such work... shall be deemed to constitute an act of copyright infringement, but only if the person committing such act of exploitation was aware of such infringement at the time of acquiring the title to exploit such copy."

This means that if a business uses software that was illicitly copied, and the business knew it was an infringing copy when they obtained the right to use it (e.g., purchased a pirated version), then the act of using that software in their business operations is itself a copyright infringement. This targets end-user piracy in commercial settings.

A critical distinction in software copyright is between the program code itself and the audiovisual output or other content generated by the program when it executes (e.g., the screen displays, graphics, and sounds of a video game, or the layout of a report generated by business software).

These are generally considered separate copyrighted works, each with its own potential for protection, authorship, and infringement analysis:

  • Program Code: Protected as a literary work (specifically, a program work).
  • Audiovisual Output: If it meets the criteria for copyrightability (e.g., creative screen displays, original graphics, music), it can be protected as an audiovisual work, a cinematographic work (as video games often are in Japan), an artistic work, or a musical work, as appropriate.

This separation means:

  • Different Authors: The author of the program code (often the employer under Article 15(2)) might be different from the author(s) of the visual graphics or music incorporated into the program's output.
  • Different Durations of Protection: The audiovisual output of a video game, if considered a cinematographic work, has its copyright term calculated from publication (70 years post-publication - Article 54), while the underlying program code, if authored by a juridical person, also typically runs for 70 years from publication (Article 53).
  • Independent Infringement: Copying the program code is an infringement of the program copyright. Separately, reproducing the unique screen displays or characters of a game could be an infringement of the copyright in the audiovisual work, even if the underlying code is not copied. The Supreme Court decision in the Used Game Soft Osaka case (April 25, 2002) treated the audiovisual output of game software as a "cinematographic work" for the purposes of the right of distribution, distinct from the underlying program.

Reverse Engineering of Software

Reverse engineering, such as decompiling object code to understand a program's structure or algorithms, can involve acts of reproduction and adaptation, potentially implicating copyright. For many years, the legality of reverse engineering for purposes like achieving interoperability or analyzing unpatented ideas was a grey area under Japanese copyright law.

The 2018 introduction of Article 30-4 (exploitation not for enjoyment) provides a more explicit potential legal basis for certain reverse engineering activities. If the purpose of decompiling and analyzing a program is for "information analysis" (as defined in Article 30-4(ii)) – for instance, to understand its internal workings for research, interoperability, or security analysis, rather than to "enjoy" its expressive code or to create a competing product by copying its expression – then such acts of reproduction and adaptation might be permissible, provided they are within the "necessary extent" and do not "unreasonably prejudice the interests of the copyright owner." This is a developing area, but Article 30-4 offers a more direct avenue for justifying such analytical uses than was previously available.

Practical Implications for Software Businesses

The specific rules for computer programs in Japan have several practical consequences:

  • Employment Contracts: Clear terms regarding authorship and rights in software developed by employees are vital, even with the default employer-authorship rule of Article 15(2).
  • Software Licensing: Licenses should clearly define permitted uses, modifications, and installations, keeping in mind the user rights under Article 47-3.
  • Moral Rights: While the right of integrity for programs is significantly limited by Article 20(2)(iii), employers who are authors under Article 15(2) should be aware they hold these (albeit limited) moral rights.
  • Compliance: Businesses must ensure they are using legitimately acquired software copies, especially in light of Article 113(2).
  • Distinguishing Code from Output: When licensing or acquiring rights related to software that generates distinct audiovisual or other content, ensure that rights to both the program and its output are adequately addressed.

Conclusion

Japanese copyright law provides a specialized regime for computer programs that attempts to balance the need to protect software developers' investments and creative expression with the practical realities of software use, modification, and development. Key features like the modified Shokumu Chosaku rule for authorship, the broad exception to the right of integrity, and specific user rights for lawful possessors of program copies distinguish software from other types of copyrighted works. For businesses in the technology sector, a nuanced understanding of these unique rules is essential for protecting their own software assets and ensuring compliance when using third-party programs in Japan.