Bradley T. Borden (Washburn) has published The Federal Definition of Tax Partnership, 43 Hous. L. Rev. 925 (2006). Here is the abstract:

The federal definition of tax partnership determines who will be subject to partnership tax law and thereby significantly impacts many taxpayers’ tax liability. Despite this, the definition remains uncertain. This Article posits that the uncertainty flows from an uncoordinated effort to define tax partnership in the absence of tax policy considerations. Partnership tax policy first disregards partnerships for tax purposes. Only when partnership tax accounting and reporting become complex and tax administration becomes inconvenient does Congress impose partnership tax rules. Although the definition of tax partnership should consider this, Congress has not explicitly defined tax partnership. Furthermore, courts, Treasury, and the IRS generally have not considered the purposes of partnership tax law in the more than 150 instances they have interpreted and applied the definition of tax partnership. As a result, those efforts have produced ten separate tests for defining tax partnership, perpetuating the definition’s uncertainty. This Article identifies and evaluates each of those tests and recommends abandoning tests that do not incorporate the purposes of partnership tax law and consolidating the remaining tests. Based on that consolidation, the Article proposes a new definition of tax partnership. The proposed definition incorporates the purposes of partnership tax law, and, because partnership tax law was intended to govern substantive-law partnerships, it includes some aspects of the substantive-law definition. Nonetheless, by using tax-specific terminology and relying on the purposes of partnership tax law, the proposal clarifies the definition of tax partnership and moves away from the substantive-law definition.