(9)The legally binding requirements in the USA with respect to derivative contracts cleared by DCOs therefore comprise a two-tiered structure. The primary rules for SIDCOs and opt-in DCOs comprise the first tier of the legally binding requirements. The internal rules and procedures of the SIDCOs and opt-in DCOs comprise the second tier of the legally binding requirements. When determining equivalence in accordance with Article 25(6) of Regulation (EU) No 648/2012, the nature and detail of the legal requirements contained within the internal rules and procedures of SIDCOs and opt-in DCOs must, therefore, be considered alongside the primary rules in order to ensure that the legally binding requirements effected through those combined components of the legal and supervisory arrangements can be considered equivalent to the requirements laid down in Title IV of Regulation (EU) No 648/2012.