This decision formally requests members to consider certain guidelines when developing their rules of origin frameworks for least developed countries, it was, however, not legally binding. Building upon the 2013 guidelines, the LDC Group introduced a proposal on 20 October 2015 for consideration in the Nairobi Ministerial Conference. The LDC Group proposal calls for the adoption of a number of changes to make it easier to comply with preferential rules of origin. For instance, it specifies simple and transparent methods for determining "substantial transformation", and asks for additional "cumulation" possibilities. In addition, it also seeks to simplify documentary elements by, for instance, proposing to abolish certain certificates of non-manipulation, and recognizing self-certification of origin. While members have said they are ready to work with the LDC Group on the issue in a constructive manner, several have expressed concerned that the proposal appears to call for binding rules whereas the Bali Decision granted countries flexibility in the application of the guidelines.