So you need to complete 8960 if your MAGI is over the threshold even if you have no investment income? In the IRS's form instructions under Application to Individuals it says "Individuals who have for the tax year (a) MAGI that’s over an applicable threshold amount, and (b) net investment income, must pay 3.8% of the smaller of (a) or (b) as their NIIT. The "and" would seem to indicate that both "a" and "b" are required before needed to complete this form. Why would you need to complete a form to calculate the tax on your investment income if you do not have any?
