be treated as meeting the age requirement of subparagraph (A) if the taxpayer or the taxpayer's spouse meets such age requirement. (5) Multiple purchasers If two or more individuals who are not married purchase a principal residence, the amount of the credit under subsection (a) shall be allocated among such individuals in such manner as the Secretary may prescribe by taking into account the requirements of paragraphs (2) and (3), except that the total amount of the credits allowed to all such individuals shall not exceed $10,000. (6) Married couples must file joint return If an individual is married at the close of the taxable year, the credit shall be allowed under subsection (a) only if the individual and the individual's spouse file a joint return for the taxable year. (c) Definitions For purposes of this section— (1) First-time homebuyer (A) In general The term first-time homebuyer means any individual who acquires a principal residence by purchase if such individual (and, if married, such individual's spouse)— (i) has not claimed any credit or deduction under this title for any previous taxable year with respect to the purchase or ownership of any residence or residential real estate (including for any expenditures relating to the placing in service of any property on, in connection with, or for use in such a residence or real estate), and (ii) attests under penalty of perjury that— (I) the individual (and, if married, the individual's spouse) has not owned a principal residence at any time prior to the purchase of the principal residence to which this section applies, and (II) the principal residence to which this section applies was not acquired from a person related to such individual or spouse. (B) Waiver in case of certain changes in status The Secretary may, in such manner as the Secretary may prescribe, waive the requirements of subparagraph (A) for a taxable year in the case of an individual who is not eligible to file a joint return for the taxable year, and who was married at the time the