The mechanism: In July 2023, U.S. regulators proposed a Basel III "Endgame" that would have raised aggregate capital requirements for large banks by roughly 16-19%, applying tougher credit-risk, operational-risk, and market-risk math to virtually every bank over $100 billion in assets. Regional banks howled. In September 2024, Fed Vice Chair for Supervision Michael Barr announced a re-proposal that cut the aggregate increase to roughly 9% — and, critically, restructured who pays it. Banks with $100-250 billion in assets — the tier that populates most of the SPDR S&P Regional Banking ETF (KRE) — would no longer be subject to the expanded credit-risk and operational-risk frameworks at all, facing only a narrower requirement to reflect unrealized securities gains/losses in capital. G-SIBs kept the roughly 9% CET1 hit. That's a bifurcation, not just a softening: the regionals' capital math improved disproportionately relative to Wall Street's giants, freeing up buyback and dividend capacity that equity markets were slow to reprice into regional bank multiples.