Why Japanese Companies Do So Many Different Things

japancorporate-governancekeiretsudiversificationlifetime-employment

Bottom line

Japanese corporate diversification is primarily driven by lifetime employment commitments operating within keiretsu (interlocking corporate networks) that insulate firms from shareholder pressure. The system incentivizes companies to expand into new industries to provide lifelong jobs for their workforce, channel surplus capital into growth opportunities, and maintain group stability. This model powered Japan's post-war economic miracle but is now declining due to corporate governance reforms and foreign investor pressure demanding shareholder returns.

Key findings

  • Core driver: Lifetime employment - Japanese firms guarantee jobs for life to many employees. When those employees' skills become obsolete or a business declines, diversification creates new roles internally rather than through layoffs.
  • Keiretsu networks enable diversification - Horizontal keiretsu (bank-centered cross-shareholdings across industries) and vertical keiretsu (supplier-manufacturer-distributor chains) provide capital, distribution, and stable partnerships to enter new sectors with lower risk.
  • Employee-run governance - Traditional Japanese boards consist of insiders; the firm exists to continue existing, not maximize shareholder profit. Diversification is a survival strategy for the corporate entity and its workforce.
  • Generalist workforce - Lifetime employment creates firm-specific, not industry-specific, skills. This makes it easier to redeploy people into new business lines.
  • Low profitability pressure - Keiretsu insulation from hostile takeovers and short-term earnings pressure allows companies to invest in long-term, potentially unprofitable diversification.

Background

Japanese corporate structure evolved from zaibatsu (pre-WWII family-controlled industrial monopolies) into keiretsu (post-WWII interlocking shareholding networks) after U.S. Occupation authorities partially dissolved the zaibatsu.

Two keiretsu types:

  • Horizontal - Bank-centered, cross-industry shareholding (Mitsubishi, Mitsui, Sumitomo, etc.)
  • Vertical - Supply chain networks (Toyota keiretsu with tiered suppliers)

The keiretsu system dominated the Japanese economy from the 1950s–1980s and is credited with enabling Japan's post-war "Economic Miracle." At peak (1988), over half the total value of the Japanese stock market consisted of cross-shareholdings.

Sources: Keiretsu – Wikipedia; Understanding Japanese Keiretsu – Investopedia; A Historical Perspective on the Japanese Keiretsu – Boston University

Current state

Keiretsu and cross-shareholding are in decline:

  • Cross-held shares dropped below 10% of all Japanese stock holdings in 2017 - from over 50% in the 1980s
  • The 2015 Japanese Corporate Governance Code required listed companies to either reduce cross-shareholdings or publicly justify them
  • Foreign investors hold >30% of Japanese equities and are pushing for American-style shareholder primacy
  • Board independence quadrupled from ~8% to ~32% (2003–2020)
  • ROE nearly doubled (3.45% to 7.09%) as firms focused on profitability

Diversification trends (RIETI/MOF data):

  • Diversification peaked in the 1990s, collapsed sharply after 2003
  • By 2014, non-manufacturing firms had highest diversification rates (real estate, retail/wholesale, services)
  • Manufacturers primarily diversified within manufacturing
  • Diversified firms showed lower current productivity but higher long-term productivity growth

Sources: Increasing Shareholder Focus: 2015 Corporate Governance Reform – PMC/Journal of Management and Governance; Diversified Firms and Productivity in Japan – MOF Public Policy Review 2017; Business Diversification/De-diversification of Japanese Companies – RIETI 1999; A Historical Perspective on the Japanese Keiretsu – Boston University

Technical / implementation details

Cross-shareholding mechanics:

  • Bank holds small stakes in member firms; member firms hold stakes in bank
  • Creates mutual financial alignment, monitors borrowings, prevents hostile takeovers
  • Intra-group trade, shared directors, worker transfers

Lifetime employment structure:

  • Seniority-based wage system (nenkō joretsu)
  • Mandatory retirement at relatively young age to manage costs
  • Firm-specific human capital investment (skills not transferable)
  • Unions organized at firm level, not industry level - weakens collective bargaining

Diversification definition in official statistics:

  • Japanese Ministry of Finance Financial Statements Statistics of Corporations by Industry: a firm is "diversified" if it reports second industry sales
  • Pre-2003: second industry sales weren't formally required; post-2003 data is more granular and reliable

Sources: Corporate Diversification, Employee Bargaining Power, and Wages – RIETI 2016; Lifetime Employment: Labor Peace and the Evolution of Japanese Corporate Governance – Columbia Law Review 1999; Keiretsu – Wikipedia

Evidence, comparisons, and related context

Empirical support for the lifetime employment → diversification link:

  • RIETI (2016): "Corporate Diversification, Employee Bargaining Power, and Wages" - diversified firms pay 10–12% higher wages to unionized workers; nonunionized workers see lower wages in diversified firms
  • MOF (2017): "Diversified firms and Productivity in Japan" - diversification associated with lower current productivity but higher long-term growth, especially for firms with greater management divisions
  • Columbia Law (1999): "Lifetime Employment: Labor Peace and the Evolution of Japanese Corporate Governance" - challenges the "bright side" narrative; argues constricted external labor markets, not secure employment, drove firm-specific human capital investment

Comparative context:

  • U.S. Conglomerates (1960s) were driven by low interest rates and used buyouts, not employment commitments - they collapsed when rates rose
  • Korean chaebol share similar over-diversification patterns but with family control rather than keiretsu networks
  • Chinese conglomerates (BYD, Huawei, Tencent) combine state/private capital with diversification strategies

Sources: RIETI 2016; MOF 2017; Columbia Law Review 1999; Conglomerate (company) – Wikipedia

Limitations and critiques

Evidence quality caveats:

  • Most Japanese corporate data pre-dates 2003 is inconsistent for diversification measurement (second industry reporting not mandatory)
  • Cross-sectional studies may have endogeneity concerns (diversification and performance mutually determined)
  • Cultural explanations (wa, consensus) are descriptive and not easily quantifiable

Performance critiques:

  • Diversified Japanese firms trade at a 6–7% valuation discount vs focused firms
  • Corporate governance reforms increased profitability and shareholder payouts, but came with reduced employment creation at large firms
  • Excessive diversification without focus can lead to resource dispersion and operational complexity - heightened during COVID-19

Path-dependency critique:

  • Columbia Law (1999) argues lifetime employment originated from political goals (defeating unions, preventing socialist electoral wins), not economic efficiency - diversification may be an adaptation to this institutional legacy, not a rationally optimal strategy

Sources: Diversification Discount and Corporate Governance in Japan (IDEAS); Increasing Shareholder Focus – PMC; Corporate Diversification and Internationalization in Japanese Manufacturing 2025 (MMRC)

Open questions

  • What is the long-run impact of governance reform on the diversification rate? Early 2010s data shows de-diversification, but post-2020 data is limited
  • How much of the remaining diversification represents related vs unrelated business? Related diversification into adjacent tech/vertical integration persists; unrelated conglomeration appears to be unwinding
  • Will keiretsu affiliations survive in practice even if cross-shareholdings are unwound? Informal networks may outlast formal structures

Practical takeaways

  • Diversification-as-insurance is a rational HR response to lifetime employment - companies become multi-industry not for synergy, but to keep employees employed
  • Cross-shareholding ≠ pure nepotism - keiretsu historically provided patient capital and long-term planning stability, enabling competitive advantage in global markets
  • The model is in structural decline - governance reform, foreign ownership, and activist funds are forcing Japanese firms to shed unrelated businesses and focus on shareholder returns; employment relationships are also becoming more flexible
  • Industry matters - manufacturing firms diversified within manufacturing; service firms diversified into disparate sectors. The type of diversification reveals intent