N.D. Cent. Code § 41-09-38

(3) Buyers of Accounts and Chattel Paper. Another aspect of sales of accounts and chattel paper also was implicit, and equally obvious, under former Article 9: If the buyer’s security interest is unperfected, then for purposes of determining the rights of certain third parties, the seller (debtor) is deemed to have all rights and title that the seller sold. The seller is deemed to have these rights even though, as between the parties, it has sold all its rights to the buyer. Subsection (b) makes this explicit. As a consequence of subsection (b), if the buyer’s security interest is unperfected, the seller can transfer, and the creditors of the seller can reach, the account or chattel paper as if it had not been sold.

(4) Effect of Perfection. If the security interest of a buyer of accounts or chattel paper is perfected the usual result would take effect: transferees from and creditors of the seller could not acquire an interest in the sold accounts or chattel paper. The same result would occur if payment intangibles or promissory notes were sold, inasmuch as the buyer’s security interest is automatically perfected under Section 9-309.