(taxpayer, employee of a closely held C Corporation, requested guidance on grouping activities under IRC §469, to determine whether grouping can be used to determine material participation in taxpayer's personal activities; IRS determined that taxpayer must have an ownership interest in each separate activity to be grouped as one activity per Treas. Reg. §1.469-4; additionally, for the measurement of gain or loss for the purpose of IRC §469, the combined activities of the corporation and the taxpayer's personal business activities would not constitute an “appropriate economic unit”; the purpose of Treas. Reg §1.469-4(d)(5)(ii) was not to give a special advantage to non-owner employees of closely held corporations, and this is further supported by Treas. Reg. 1.469-5(f)(1); IRS noted that if the employee performs work “in connection” with his or her other activities, that work may be counted towards material participation; taxpayer bears the burden of proof to show that the work was “in connection” with an activity in which the taxpayer owns an interest).