What’s the largest Japanese family office by AUM?

The search for the largest family office in Japan is a challenging task, as most affluent families choose to conceal their investment activities and allocate most of their wealth to family companies, which are often large corporations rather than family offices. Our experienced familyofficehub.io research team has identified the Yamauchi No.10 Family Office, the investment vehicle of the Yamauchi family, which manages over $1bn, as the largest Japanese family office.

The Yamauchi No.10 Family Office (YFO) was established in 2020 to manage the wealth and legacy of the Yamauchi family, historically known for its leadership in transforming Nintendo from a traditional playing card company into a global video game company. Founded by Banjo Yamauchi, grandson and adopted son of former Nintendo president Hiroshi Yamauchi, the office aims to continue the family’s heritage of innovation, long-term vision, and cultural relevance.

The investment focus of Yamauchi No.10

YFO manages a portfolio of nearly $1.5 billion and adopts a long-term investment approach, emphasizing the flexibility to remain engaged with companies for extended periods, often beyond a decade. This patient capital strategy enables the family office to support transformations that may take significant time to materialize, distinguishing it from more short-term-focused investors.

The office invests across both public and private equity markets, targeting sectors and companies with potential to contribute to Japan’s industrial and societal renewal. About half of its assets are allocated to roughly two dozen projects in next-generation technologies, including sectors such as artificial intelligence, healthcare innovation, and space-related services like space debris clean-up.

A defining characteristic of YFO’s investment activity is its willingness to engage directly with portfolio companies. One prominent example is its ongoing involvement with Toyo Construction Co., a Japanese marine construction firm. YFO, which holds a significant minority stake in the company, has raised concerns about governance and oversight practices and has actively submitted proposals for operational and leadership reform. These efforts reflect the office’s belief in constructive activism as a tool to drive better long-term outcomes in companies with underutilized potential.

In 2023, YFO entered into a strategic partnership with Taiyo Pacific Partners, a U.S.-based investment firm known for its focus on Japanese and Indian equities. The partnership merges Taiyo’s investment strategies with the Yamauchi family office’s creative and legacy-driven perspective. As part of the integration, YFO’s Chief Investment Officer, Hirowaka Murakami, now serves as Co-CEO of the combined entity. The collaboration is intended to enhance the reach and impact of both organizations in revitalizing legacy companies and supporting emerging ventures in Japan.

The ethos of the Yamauchi No.10 Family Office is deeply shaped by the legacy of Hiroshi Yamauchi, who led Nintendo for over five decades and played a pivotal role in the development of the modern video game industry. The family office reflects this heritage in both its branding and philosophy, maintaining a symbolic connection to Nintendo’s early innovations through design elements, such as 8-bit aesthetics and references to traditional hanafuda cards.

Alternative candidates for the Japan family office ranking by AUM

Our familyofficehub.io family office research team has considered multiple candidates in the scope of the families. To the extent of our knowledge, the richest Japanese citizen, Tadashi Yanai, has no proper family office structure but instead has concentrated its wealth within Fast Retailing. The same goes for Takemitsu Takizaki with Keyence. The closest competitor was Masayoshi Son, whose Softbank Vision fund is often interpreted as a family office. However, Softbank is stock-listed, which speaks against the traditional family office model. In addition, the SoftBank Vision fund has multiple outside investors, which is also a strong argument against listing it as the largest Japanese family office. Hence, we see Yamauchi No.10 as the clearest pick for our ranking.

Picture Source: Getty Images, Unsplash+ (29.04.2025)