Adjustment for gift tax paid by spouse
For purposes of subsection (b)(2), if—
(1)#
the decedent was the donor of any gift one-half of which was considered under section 2513 as made by the decedent’s spouse, and
(2)#
the amount of such gift is includible in the gross estate of the decedent,
any tax payable by the spouse under chapter 12 on such gift (as determined under section 2012(d)) shall be treated as a tax payable with respect to a gift made by the decedent.