FRTB

The Fundamental Review of the Trading Book (FRTB), is a set of proposals by the Basel Committee on Banking Supervision for a new market risk-related capital requirement for banks. [1][2] This reform, often referred to as "Basel IV", is one of the initiatives taken to strengthen the financial system, noting that the previous proposals (Basel II) did not prevent the financial crisis of 2007–2008. [3][4] It was initially published in January 2016 [5] and revised in January 2019. [6]

See also: Market risk #Regulatory views

The FRTB revisions address deficiencies relating to the existing Standardised approach[7] and Internal models approach[7][8] and particularly revisit the following:

• The boundary between the "trading book" and the "banking book": i.e. assets intended for active trading; as opposed to assets expected to be held to maturity, usually customer loans, and deposits from retail and corporate customers [9] (important since the "[v]ast majority of losses were from trading books during the 2008 crisis"[1])
• The use of expected shortfall vs. value at risk as a measure of risk under stress; thus ensuring that banks capture tail risk events
• The risk of market illiquidity

FRTB sets a "higher bar" for banks to use their own, internal models for calculating capital, as opposed to the standardised approach.[2] The Logic: the standardised approach is directly implementable, but, at the same time, carries more capital; the internal models approach, by contrast, carries less capital, but the modelling is more complex, requiring that expected shortfall is applied, together with add-ons for the "non-modellable risk factors" that lack sufficient data. Given this complexity, for a desk to qualify for the internal models approach, its model must pass two tests: a profit and loss attribution test and a backtest.