RBI has issued new norms aligning India's banking framework with Basel III standards for market risk capital requirements. A key provision bars banks from reclassifying financial instruments into categories that attract lower capital charges, effective April 1, 2027. The guidelines introduce a revised approach to calculating capital against trading book exposures, tightening the boundary between trading and banking books to prevent regulatory arbitrage and strengthen overall bank resilience to market volatility.

Market risk refers to the risk of losses in a bank's trading portfolio due to movements in interest rates, equity prices, foreign exchange rates, or commodity prices. Basel III's Fundamental Review of the Trading Book (FRTB) is the global framework that overhauled how banks calculate capital for market risk.

The core concept here is the trading book versus banking book boundary. Banks hold some assets in the 'trading book' (marked to market daily, intended for short-term trading) and others in the 'banking book' (held to maturity, subject to credit risk capital). Historically, banks exploited this boundary — shifting instruments to whichever book required less capital. The new RBI norms directly plug this gap.

The reclassification prohibition effective April 1, 2027, means that once an instrument is assigned to a book, it cannot be moved to game the capital calculation. This is a structural safeguard against regulatory arbitrage.

For capital adequacy, banks are required to maintain capital against risk-weighted assets (RWAs). Under market risk rules, instruments in the trading book attract capital based on Standardised Approach or Internal Models Approach. Tightening the book boundary raises the quality and quantity of capital banks must hold, making them more resilient to sudden market shocks.

For RBI Grade B aspirants, this connects directly to Basel III pillars, the Capital Adequacy Ratio (CAR) framework, and RBI's role as the prudential regulator implementing international standards domestically.