In this situation, the LLC, which, for federal tax purposes, is disregarded as an entity separate from its owners, is converted to a partnership when the new member, B, purchases an interest in the disregarded entity from the owner, A. B's purchase of 50% of A's ownership interest in the LLC is treated as the purchase of a 50% interest in each of the LLC's assets, which are treated as held directly by A for federal tax purposes. Immediately thereafter, A and B are treated as contributing their respective interests in those assets to a partnership in exchange for ownership interests in the partnership.
Under §1001, A recognizes gain or loss from the deemed sale of the 50% interest in each asset of the LLC to B.
Under § 721(a), no gain or loss is recognized by A or B as a result of the conversion of the disregarded entity to a partnership.
Under § 722, B's basis in the partnership interest is equal to $5,000, the amount paid by B to A for the assets which B is deemed to contribute to the newly-created partnership. A's basis in the partnership interest is equal to A's basis in A's 50% share of the assets of the LLC.
Under §723. the basis of the property treated as contributed to the partnership by A and B is the adjusted basis of that property in A's and B's hands immediately after the deemed sale.
Under § 1223(1), A's holding period for the partnership interest received includes A's holding period in the capital assets and property described in §1231 held by the LLC when it converted from an entity that was disregarded as an entity separate from A to a partnership. B's holding period for the partnership interest begins on the day following the date of B's purchase of the LLC interest from A. Under §1223(2), the partnership's holding period for the assets deemed transferred to it includes A's and B's holding period for such assets.