I have a trading loss from a S corp that is engaged in a trade or business of trading financial instruments or commodities. The loss shows up on Line 4a, but is then backed out on Line 4b, so it's not reducing my total investment income subject to NIIT. How do I indicate that the S corp is engaged in the business of trading financial instruments so that it doesn't get backed out on line 4b? I believe 4b is meant to back out S corps unrelated to trading.
Line 4b—Adjustment for Net Income or Loss Derived in the Ordinary Course of a Non-Section 1411 Trade or Business
Use line 4b to adjust the amounts included on line 4a, for gains and losses that are excluded from the calculation of net investment income. Enter the amount of gains (as a negative number) and losses (as a positive number). Enter the net positive or net negative amount for the following items included on line 4a that aren’t included in determining net investment income.
Net income or loss from a section 162 trade or business that’s not a passive activity and isn’t engaged in a trade or business of trading financial instruments or commodities.
Net income or loss from a section 1411 trade or business that’s taken into account in determining self-employment income.
Royalties derived in the ordinary course of a section 162 trade or business that’s not a passive activity.
Passive losses of a former passive activity that are allowed as a deduction in the current year under section 469(f)(1)(A).
