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Fannie Mae Single Family Servicing Guide
If a mortgage loan not subject to a due-on-sale (or due-on-transfer) provision is modified, the servicer must obtain the borrower’s agreement that the mortgage loan modification will cancel the assumability feature of that mortgage loan. See D1-4.2-02, Conventional Mortgage Loans That Include a Due- on-Sale (or Due-on-Transfer) Provision for additional information.
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