National Internal Revenue Code (NIRC)
Section 100. Transfer for Less Than Adequate and full Consideration. - Where property, other than real property referred to in Section 24(D), is transferred for less than an adequate and full consideration in money or money's worth, then the amount by which the fair market value of the property exceeded the value of the consideration shall, for the purpose of the tax imposed by this Chapter, be deemed a gift, and shall be included in computing the amount of gifts made during the calendar year.