The Internal Logic of Japanese Corporate Diversification

 Why Japanese companies do so many different things The internal logic of the world’s strangest corporations David Oks, May 18, 2026

Consider Toto. While famous for its serif-font logo and dominating 80 percent of the Japanese bidet-toilet market, the company is currently experiencing a remarkably lucrative year in 2026 that has little to do with bathroom fixtures. While Toto was founded in the 1910s to provide affordable toilets, it now manufactures tiles, faucets, modular kitchens, and assistive equipment for the elderly. Most importantly, it has a lucrative sideline in the advanced ceramics division producing the electrostatic chuck (e-chuck). This ceramic plate uses electrostatic force to hold silicon wafers flat during memory chip etching—a process so difficult that only a few companies, mostly Japanese, can reliably manufacture them. Due to the exploding demand for AI, Toto’s ceramics division has become its largest business and primary profit driver.

This diversification is not unique to Toto; practically every major Japanese company operates across vast, seemingly unrelated industries. Kyocera, founded for ceramic insulators, now makes everything from smartphones to lab-grown gemstones. Sumitomo Osaka Cement produces both concrete and cosmetics. Yamaha manufactures pianos, motorcycles, and industrial robots, while Hitachi makes nuclear reactors, elevators, and IT consulting services. Even Oji, a paper company, operates hotels and an insurance agency.

Unlike the sprawling conglomerates in developing nations like India, Japanese firms are striking because they perform these diverse, high-precision tasks exceptionally well. This contrasts sharply with American firms that prioritize focus, or even German and South Korean models. The author suggests that Japanese companies excel in these different domains because it is inherent in their structure—they are a "different species" of corporation adapted to a specific environment.

Companies are bundles of practices

Economists Paul Milgrom and John Roberts argued in 1990 that modern manufacturing practices work as complementary bundles. Adopting one practice, such as shorter production runs, makes other practices, like reducing inventory or investing in flexible machinery, more valuable. These practices are worth more as a complete set than as isolated parts. This framework explains why it is so difficult for firms to change: changing one practice without the rest of the bundle often makes the firm worse off. Economist Masahiko Aoki used this to describe the "J-firm" bundle.

Japanese companies are nothing like American ones

The J-firm bundle is defined by several distinctive features:

• Lifetime Employment: Firms hire recruits straight from school and keep them until retirement; mass layoffs are unheard of.
• Seniority-Based Pay: Promotions and pay are based on tenure rather than individual performance.
• Horizontal Coordination: Unlike the vertical hierarchy of "H-firms" (American/European), Japanese firms use lateral information flows. A prime example is the andon cord in Toyota factories, which allows any worker to halt production to fix a defect.
• Insulation from Outsiders: Boards are dominated by internal managers, and equity is often cross-held by other Japanese firms and a "main bank".

This system requires generalist workers who rotate through different functions, which only makes sense if those workers are guaranteed long-term employment. Because J-firms are run by employees and are largely indifferent to shareholders, they exist simply to continue existing. This survival instinct drives their insistent diversification; if a current product line fails, the firm pivots to new markets to keep its lifetime employees busy. For example, Nintendo moved from playing cards to video games, and Fujifilm pivoted from film to cosmetics and pharmaceuticals.

Bundles are hard to make and hard to unmake

The Japanese bundle was established during the crisis of the Second World War. In the 1920s, the Japanese economy functioned much like the American one, with shareholder discipline and mobile labor. However, the "1940 system" reworked the economy for total war, prioritizing production and employees over shareholders and rerouting capital through banks. This system survived the war and proved exceptionally good at catch-up growth.

The J-mode has a comparative advantage in moderate volatility, where incremental refinements are necessary. However, it struggles with paradigm invention and sharp discontinuity. While Sony had all the components for a smartphone, it was the vision-led "H-firm" Apple that reimagined the product category.

Following the 1990 asset bubble collapse, Japanese "zombie" companies soldiered on, as mass layoffs would have undermined the social settlement. Attempts at reform, such as Fujitsu's failed experiment with performance-based pay in the 1990s, often fail because they do not cohere with the rest of the organizational bundle. Despite these challenges, the deep process knowledge within the Japanese system remains a critical, non-entrepreneurial partner to the American innovation-led system, particularly in the semiconductor supply chain.