A sponsor is an important part of many US immigration processes. For example, the sponsor is often the person who makes an applicant eligible for an immigrant visa and often provides a financial guarantee to the US that the applicant will not become a burden on the US special assistance system. For these reasons, it is very important for the USCIS to be apprised of the current residence of the sponsor. Under 8 U.S.C. 1183a(d), a sponsor is required to inform the USCIS of a change of address. This can be accomplished by filing USCIS Form I-865 (Sponsor's Notice of Change of Address).