Predominantly Individual Ownership
In Japan, most patent firms operate under individual ownership rather than a partnership model. While exact figures are not publicly available, it is widely understood among practitioners that true partnership-based IP firms are exceptionally rare.
In most cases, the founder of the firm serves as the principal or managing attorney, maintaining full control as a single owner. This structure is deeply rooted in Japan’s professional and business culture, where many firms have developed around the reputation and leadership of a single founder rather than a shared partnership framework.
Limited Prevalence of Patent Professional Corporations
In addition to individually owned patent firms, Japan also has a legal entity type known as a “benrishi hojin” (Patent Professional Corporation). This structure was introduced to allow for a corporate-style organization among patent attorneys.
However, according to the Distribution of Members of the Japan Patent Attorneys Association (as of February 28, 2025), only 3.58% of the total 11,782 registered patent attorneys belong to such corporations.
The reasons why patent professional corporations have not become widespread remain unclear. One possible factor is the traditionally long history of many Japanese patent firms, which have been operating as individually owned offices for decades. Transitioning to a corporate form can be administratively complex and culturally challenging. In practice, some firms choose to convert into a patent professional corporation when there is a generational shift in leadership, such as during a change of managing partner or founder succession.
Distinct Separation from General Law Firms
In Japan, it is extremely rare for general law firms and patent firms to operate as a single, unified entity. This is because the qualification and professional role of a benrishi (patent attorney) are completely separate from those of a bengoshi (attorney-at-law).
The scope of work, professional culture, and even training paths differ significantly between these two professions. As a result, it is uncommon to see large general law firms acquiring or merging with patent firms in Japan. Consequently, most patent firms in Japan operate as boutique firms dedicated exclusively to intellectual property services.
Interpreting Patent Filing Statistics in Japan
The number of published patent applications does not necessarily reflect the true size or workload of a Japanese patent firm. This is because Japan’s patent firms tend to fall into four broad categories:
- firms serving mainly domestic clients,
- firms handling primarily inbound (foreign-to-Japan) filings,
- firms that handle both, and
- firms specializing in litigation.
Importantly, published Japanese patent applications (patent publications) do not include outbound work—namely, applications filed from Japan to other countries. As a result, firms focusing on domestic clients may handle significantly more work than the publication figures alone would suggest.
Each type of patent firm plays an important role in Japan’s intellectual property ecosystem. Firms that primarily serve domestic clients (Type 1) often have strong ties to local businesses and offer practical, long-term support tailored to the Japanese market. Firms that mainly handle inbound work (Type 2) are highly experienced in navigating the Japan Patent Office system and in communicating effectively with foreign associates.
Firms that manage both domestic and inbound work (Type 3) are relatively few in number, but they are uniquely positioned to facilitate collaboration between Japanese clients and overseas attorneys, helping to align international strategies and expectations.
