Article 85
1.Without prejudice to Article 89, credit institutions and any parent undertaking and its subsidiaries shall implement the IRB Approach for all exposures.
Subject to the approval of the competent authorities, implementation may be carried out sequentially across the different exposure classes, referred to in Article 86, within the same business unit, across different business units in the same group or for the use of own estimates of LGDs or conversion factors for the calculation of risk weights for exposures to corporates, institutions, and central governments and central banks.
In the case of the retail exposure class referred to in Article 86, implementation may be carried out sequentially across the categories of exposures to which the different correlations in Annex VII, Part 1, points 10 to 13 correspond.
2.Implementation as referred to in paragraph 1 shall be carried out within a reasonable period of time to be agreed with the competent authorities. The implementation shall be carried out subject to strict conditions determined by the competent authorities. Those conditions shall be designed to ensure that the flexibility under paragraph 1 is not used selectively with the purpose of achieving reduced minimum capital requirements in respect of those exposure classes or business units that are yet to be included in the IRB Approach or in the use of own estimates of LGDs and/or conversion factors.
3.Credit institutions using the IRB Approach for any exposure class shall at the same time use the IRB Approach for the equity exposure class.
4.Subject to paragraphs 1 to 3 of this Article and Article 89, credit institutions which have obtained permission under Article 84 to use the IRB Approach shall not revert to the use of Subsection 1 for the calculation of risk-weighted exposure amounts except for demonstrated good cause and subject to the approval of the competent authorities.
5.Subject to paragraphs 1 and 2 of this Article and Article 89, credit institutions which have obtained permission under Article 87(9) to use own estimates of LGDs and conversion factors, shall not revert to the use of LGD values and conversion factors referred to in Article 87(8) except for demonstrated good cause and subject to the approval of the competent authorities.