Internal Revenue Code Section 355(b)(2)(B) provides that the active business of the distributing and controlled corporations must have been conducted for at least five years prior to the spin-off. The fact that a business has undergone changes in the five-year period is immaterial, so long as the changes are not fundamental enough to constitute the acquisition or adoption of a new business that does not satisfy the five-year period requirement. See Treas. Reg. Section 1.355-3(b)(3).