FinanceLenders' AI investments have focused on efficiency, not defenseAI tools such as Anthropic's Mythos may be able to expose major weaknesses in banks' digital architecture. (Photo by Suzu Takahashi)KAI ISHIZAKIMay 21, 2026 01:32 JSTTOKYO -- The emergence of Anthropic's Claude Mythos artificial intelligence tool is confronting top Japanese banks with new risks to digital investment strategies that had focused on increasing efficiency and revenue.Read NextArtificial intelligenceHitachi teams with Anthropic on AI for rail and power gridsTechnologyAnthropic weighs taking part in Japan cyber defense allianceFinanceJapan banks eye Anthropic's Mythos in gearing up cybersecurity driveArtificial intelligenceJapan to craft cyberdefense guidelines in response to Anthropic's MythosArtificial intelligenceGoogle says new AI model could save companies billions in token costsFinanceTop Japan banks' profits hit record on M&A lending boomArtificial intelligenceJapan's MUFG taps Google's Gemini AI to help customers shop, saveInterviewPeople are a 'bottleneck' to AI-led efficiency gains: LY chairLatest on FinanceFinanceJapan's DBJ eyes longer investment horizon to support reshoringFinanceDaiwa to take stake in Airborne Capital to grow aircraft lease investmentsFinanceBain Capital's $10.5bn Asia fund to invest half in Japan