A taxpayer may use the method provided in subsection (b) (whether or not such method has been prescribed under section 471) in inventorying goods specified in an application to use such method filed at such time and in such manner as the Secretary may prescribe. The change to, and the use of, such method shall be in accordance with such regulations as the Secretary may prescribe as necessary in order that the use of such method may clearly reflect income.
The beginning inventory for the first taxable year for which the method described in subsection (b) is used shall be valued at cost. Any change in the inventory amount resulting from the application of the preceding sentence shall be taken into account ratably in each of the 3 taxable years beginning with the first taxable year for which the method described in subsection (b) is first used.
The Secretary shall prescribe regulations permitting the use of suitable published governmental indexes in such manner and circumstances as determined by the Secretary for purposes of the method described in subsection (b).
Except as otherwise provided in regulations, all members of the same group of financially related corporations shall be treated as 1 taxpayer for purposes of subsections (c) and (e)(2).