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26 U.S. Code § 733 - Basis of distributee partner’s interest

In the case of a distribution by a partnership to a partner other than in liquidation of a partner’s interest, the adjusted basis to such partner of his interest in the partnership shall be reduced (but not below zero) by—
the amount of any money distributed to such partner, and
the amount of the basis to such partner of distributed property other than money, as determined under section 732.
(Aug. 16, 1954, ch. 736, 68A Stat. 247.)