See https://www.irs.gov/instructions/i8960#en_US_2022_publink10003330
Generally, net gain from the disposition of property not used in a trade or business and net gain or loss from the disposition of property held in a section 1411 trade or business is included in net investment income if included in taxable income.
Note:
Section 1411 trade or business.
Generally, a trade or business that’s either a passive activity for the taxpayer or is a trade or business of trading in financial instruments or commodities. See section 1411(c)(2) and Regulations section 1.1411-5(a).
