(4)The scope of this Regulation should be as broad as possible to provide for a preventive regulatory framework to be used in exceptional circumstances. That framework should cover all financial instruments but should provide for a proportionate response to the risks that short selling of different instruments could represent. It is therefore only in the case of exceptional circumstances that competent authorities and ESMA should be entitled to take measures concerning all types of financial instruments, going beyond the permanent measures that only apply to particular types of instruments where there are clearly identified risks that need to be addressed.