(16)Regulation (EU) No 462/2013 introduces safeguards in Article 8(5a)(6) aa and ab and (7) of Regulation (EC) No 1060/2009 to ensure that any modification to rating methodologies does not result in less rigorous methodologies. The Mexican legal and supervisory framework requires CRAs to publish on its website methodologies and procedures used for the research, analysis, opinion, evaluation and consideration of credit quality, before they are used, and must disclose any material change to their methodologies, so they can be consulted by the investing public. In the same way, CRAs are required to review their methodologies and models, although there is no an explicit requirement to conduct a consultation with market participants prior to a change in their methodology and to address errors identified in their methodologies. However, in case the CRA introduces significant changes to the rating methodologies, the CRA has to notify to CNBV regarding the amendments introduced into the rating methodology and disclose them to the public without revealing the reason thereof. In case there is an amendment to the CRA's rating models and methodologies, the CRA has to review all ratings previously issued.