(a) A business is unitary if the entity or entities involved are owned, centrally managed, or controlled, directly or indirectly, under one common direction which can be formal or informal, direct or indirect, or if the operation of the portion of the business done within the state is dependent upon or contributes to the operation of the business outside the state.
(b) The unitary nature of a business is a case-by-case factual determination and applicable statutes, regulations, and administrative and judicial precedent will be used as guidelines for making the determination.
(c) If a corporation is owned by a sovereign, head of state, government, or governmental agency, the unitary business does not include the sovereign, head of state, government, or governmental agency for purposes of this chapter.