If community property laws apply to income that an individual derives from a trade or business (other than a trade or business carried on by a partnership), the gross income and deductions attributable to such trade or business shall be treated as the gross income and deductions of the spouse carrying on such trade or business or, if such trade or business is jointly operated, treated as the gross income and deductions of each spouse on the basis of his or her respective distributive share of the gross income and deductions. [70 FR 41955, July 21, 2005]