N.D. Cent. Code § 6-05.2-05
Uninvested or undistributed funds held by a banking institution in a fiduciary capacity must not be held uninvested or undistributed any longer than is reasonable for the proper management of the account. Each banking institution exercising fiduciary powers must adopt and follow written policies and procedures intended to ensure that the maximum rate of return available for trust-quality, short-term investments is obtained consistent with the requirements of the governing instrument or law. The policies and procedures must take into consideration all relevant factors, including the anticipated return that could be obtained while the cash remains uninvested or undistributed, the cost of investing the funds, and the anticipated need for the funds.
N.D.C.C. § 6-05.2-05