The main purpose of this legislation is to update the tax rules regarding the sale of personal property in U.S. territories. Specifically, it aims to clarify how income from these sales is taxed, ensuring that the tax treatment is consistent across different U.S. possessions. The key provision of this legislation modifies existing tax rules by adding a reference to a specific section of the Internal Revenue Code. This change means that income from personal property sales in certain U.S. territories will be treated similarly to income from sales in other areas, promoting fairness in taxation.