1. When withdrawals are made from IRA's they are reported to the IRS under your name & SS#. Same is true for conversions & when RMD's are required, each institution informs of the balance & the RMD required. And you as an individual report the amt. of withdrawals & conversions on your tax forms. However, with the UBTI, each institution, not you, must file the tax form & pay the tax, if it is required, from the IRA. Quite different.,
Anyway, I have no informed opinion on this. I merely reprinted a post from a tax accountant who cited several IRC regs. & concluded that UBTI is computed separately.
My main point was to clarify the issue of whether UBTI of $1000 or more triggered a taxable event if no one mlp generated that amt. I wanted to point out that it was an aggregate of mlps & not just one in an IRA. And wanted to point out that negative #'s from one mlp can't offset positive #'s in another.