Idaho Code § 32-913
Whenever payment or refund is made to an employee, former employee, or such person's beneficiary or heirs, legatees or estate pursuant to a written retirement, death, stock, or other employee benefit plan or savings plan such payment or refund shall fully discharge the employer, former employer, and any trustee or insurance company making such payment or refund from all adverse claims thereto unless such payment or refund is made within twenty (20) days following the death of such employee or former employee or unless before such payment or refund is made, the employer or former employer, where the payment or refund is made by the employer or former employer, has received at its principal place of business within this state or home office, written or oral notice by or on behalf of some other person that such other person claims to be entitled to such payment or refund or some part thereof, or where a trustee or insurance company is making the payment or refund, such notice has been received by the trustee or insurance company at its home office or its principal place of business within this state. Should said payment or refund be comprised in whole or in part of stock of any corporation, such corporation may accept said stock for transfer as directed by the employer, former employer, or the trustee making such payment or refund, and shall be entitled to treat the transferee as the owner of said stock for all purposes unless the corporation has received, at its home office, written or oral notice by or on behalf of some other person that such other person claims to be entitled to such stock or to some interest therein. This section shall not affect any claim or right to any such payment or refund or part thereof as between all persons other than the employer or former employer and the trustee or insurance company making such payment or refund or the corporation accepting such stock for transfer.
Idaho Code § 32-913