Which life insurance policy provision prohibits a beneficiary from "commuting, encumbering, withdrawing, or assigning" any portion of the proceeds prior to actual receipt from the company?

The specific kind of insurance policy based on the description provided by the question would be the Spendthrift clause. By definition, a spendthrift provision is a term that is used mainly to describe a provision wherein the inheritance of the benefactor is protected from being given away to another individual.