In computing the taxable income of a partner for a taxable year, the inclusions required by section 702 and section 707(c) with respect to a partnership shall be based on the income, gain, loss, deduction, or credit of the partnership for any taxable year of the partnership ending within or with the taxable year of the partner.
The taxable year of a partnership shall be determined as though the partnership were a taxpayer.
A partner may not change to a taxable year other than that of a partnership in which he is a principal partner unless he establishes, to the satisfaction of the Secretary, a business purpose therefor.
For the purpose of this subsection, a principal partner is a partner having an interest of 5 percent or more in partnership profits or capital.
The term “majority interest taxable year” means the taxable year (if any) which, on each testing day, constituted the taxable year of 1 or more partners having (on such day) an aggregate interest in partnership profits and capital of more than 50 percent.
Except as provided in regulations necessary to prevent the avoidance of this section, if, by reason of paragraph (1)(B)(i), the taxable year of a partnership is changed, such partnership shall not be required to change to another taxable year for either of the 2 taxable years following the year of change.
Except as provided in regulations, for purposes of determining the taxable year to which a partnership is required to change by reason of this subsection, changes in taxable years of other persons required by this subsection, section 441(i), section 584(i), section 644, or section 1378(a) shall be taken into account.
Except in the case of a termination of a partnership and except as provided in paragraph (2) of this subsection, the taxable year of a partnership shall not close as the result of the death of a partner, the entry of a new partner, the liquidation of a partner’s interest in the partnership, or the sale or exchange of a partner’s interest in the partnership.
The taxable year of a partnership shall close with respect to a partner whose entire interest in the partnership terminates (whether by reason of death, liquidation, or otherwise).
The taxable year of a partnership shall not close (other than at the end of a partnership’s taxable year as determined under subsection (b)(1)) with respect to a partner who sells or exchanges less than his entire interest in the partnership or with respect to a partner whose interest is reduced (whether by entry of a new partner, partial liquidation of a partner’s interest, gift, or otherwise).
Except as provided in paragraphs (2) and (3), if during any taxable year of the partnership there is a change in any partner’s interest in the partnership, each partner’s distributive share of any item of income, gain, loss, deduction, or credit of the partnership for such taxable year shall be determined by the use of any method prescribed by the Secretary by regulations which takes into account the varying interests of the partners in the partnership during such taxable year.