A real estate investment trust (REIT) is a company that owns, operates, or finances income-producing properties.
all REIT dividends, except capital gain distributions under IRC 857(b)(3) and any part of any ordinary dividend that is a qualified dividend under IRC 1(h)(11) are QBI (IRC 199A (e)(3)
some PTP's generate QBI others do not (certain investment PTPs that generate investment but not business income. with PTPs every one stands on their own for tax purposes. if you have 2 PTPs one with a business profit and one with a business loss. you are taxed on the profitable one while the loss for the other one is suspended until it either generates a profit or is disposed of. the QBI follows the treatment of the business income or loss. further, the QBI deduction for REITs and PTPs is completely separate from the QBI deduction for operating businesses that generate QBI. so in a situation where you have an operating business that has a QBI loss and you have QBI REIT dividends you get the QBI deduction for the dividends while the QBI loss for the business is suspended.