A US-based asset manager's activities were attributed to a foreign partnership and were not within any safe harbors because the activities were not limited to managing investments or trading in stocks or securities.The foreign partnership was found to be a "dealer in securities" and required to recognize gain under the "mark-to-market" rule of IRC Section 475(a)(2).Gain or loss recognized by the foreign partnership with respect to securities was treated as effectively connected income under IRC Section 864(c)(3).The period of limitation on the assessment of IRC Section 1446 withholding tax did not commence by filing IRS Form 1065 where no IRS...