Cal. Rev. & Tax. Code § 17854

For purposes of computing “taxable income of a nonresident or part-year resident” under paragraph (1) of subdivision (i) of Section 17041, in the case of a nonresident partner, guaranteed payments, as defined by Section 707(c) of the Internal Revenue Code, shall be included in that computation as gross income from sources within this state in the same manner as if those payments were a distributive share of that partnership.