The MPN is a legal document that promises to pay your loan and accrued interest and fees to the US Department of Education, it also explains the terms and conditions of your loan. Graduate / professional students may be eligible for both unsubsidized direct loans and direct PLUS loans, which have different MPNs.
And what should I use for direct PLUS loans?
Use this MPN for direct PLUS loans available to eligible graduate / professional students. You may also need to complete an MPN for unsubsidized direct loans.
and you know who should complete this?