2021 1065 Instructions (pg38/59)

Other deductions (code W).
....However, do not enter expenses related to portfolio income or investment interest expense reported on line 13b of Schedule K on this line.

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(pg39/59)

Deductions—portfolio (formerly deductible by individuals under section 67 subject to the 2% AGI floor). For partners other than individuals, amounts that are clearly and directly allocable to portfolio income (other than investment interest expense and section 212 expenses from a REMIC) can be deducted on those partners’ income tax returns