In an April 23, 2004 field memo, USCIS instructs adjudicators who are reviewing employment-based petition extensions to give deference to the eligibility determinations made in the prior petition, where the extension petition presents no material change in the underlying facts. Extension requests involving a prior material error, substantial change of circumstances, or new material that adversely impacts the petitioner’s or beneficiary’s eligibility will not benefit from such deference. AMDOC#: 200405005