Partner-level defenses.
Partner-level defenses. Partner-level defenses to any penalty, addition to tax, or additional amount that relates to an adjustment to a partnership item may not be asserted in the partnership-level proceeding, but may be asserted through separate refund actions following assessment and payment. See section 6230(c)(4). Partner-level defenses are limited to those that are personal to the partner or are dependent upon the partner's separate return and cannot be determined at the partnership level. Examples of these determinations are whether any applicable threshold underpayment of tax has been met with respect to the partner or whether the partner has met the criteria of section 6664(b) (penalties applicable only where return is filed), or section 6664(c)(1) (reasonable cause exception) subject to partnership-level determinations as to the applicability of section 6664(c)(2).