Retirement Inflation Protection Act of 201 7 This bill amends the Internal Revenue Code to allow the adjusted basis of certain assets (including common stock in a C corporation and tangible property used in a trade or business) to be indexed for inflation for the purpose of determining the gain or loss of individuals who: (1) have held the asset for more than 3 years, and (2) have attained the age of 59-1/2 as of the date of the sale or other disposition of the asset. The bill sets forth rules for applying the inflation adjustment to short sales, dispositions between related persons, and improvements to property or contributions of capital. The Internal Revenue Service may disallow an adjustment if any person transfers cash, debt, or any other property to another person for the principal purpose of securing or increasing the adjustment allowed by this bill.