2014 USDA Approved Processing Vendors Vendors wanting to process bulk USDA Foods must be approved by USDA. Vendors enter into a National Processing Agreement with USDA and are put on the NPA list. This list contains all approved vendors. Vendors must enter into a State Participation Agreement prior to processing USDA Foods. Not all approved vendors participate in the Net-Off Invoicing program. Contact your State Distributing Agency for information about the NOI program or about approved vendors.