Nomura's Chief Financial Officer emphasized critical uncertainties surrounding Japan's ultra-long-term government bonds. The warning spotlights potential turbulence in sovereign debt instruments exceeding 10-year maturities, as yield fluctuations intensify amid shifting monetary policy expectations. Market participants should monitor duration exposure carefully, the executive noted, particularly given the Bank of Japan's evolving stance on yield curve control. This caution comes as global investors reassess Japanese debt holdings following recent inflation surprises and yen volatility. Historical patterns suggest such extended maturities amplify interest rate sensitivity, creating disproportionate price swings during policy transitions. Trading desks across major institutions are reportedly adjusting hedging strategies accordingly.