When a buyer of real property gives to the seller a written contract for payment of all or part of the price, an absolute transfer of the contract by the seller waives the seller's lien to the extent of the sum payable under the contract, but a transfer of the contract in trust to pay debts and return the surplus is not a waiver of the lien.
N.D. Cent. Code § 35-20-02
Vendor's lien waived by transfer of written contract for payment - Exception
Official source: North Dakota Legislative Branch. Reproduced from public-domain North Dakota statutes; confirm against the official source for the current text. Not legal advice.