This is a structuring question. The investing member of the QOF must be the same taxpayer with the capital gain, or else the deferral probably doesn't work. You can't take an individual gain and defer it by investing in a QOF through an upper-tier partnership. That structuring basically won't fly. But the QOF itself can certainly be a tax partnership, and its subsidiary QOZB can also be a partnership. This is probably what you mean when you say investing through a partnership. The 90% test is a standard applied at the QOF level. QOZBs have their own set of compliance rules as well.