Can you tell me what it means to be an active participant?

[DavidD66]

If you are referring to rental property, You actively participated in a rental real estate activity if you (and your spouse) owned at least 10% of the rental property and you made management decisions or arranged for others to provide services (such as repairs) in a significant and bona fide sense.

[Carl]

IRS Publication 925 page 4 at https://www.irs.gov/pub/irs-pdf/p925.pdf defines active participation.

Active participation.

Active participation isn’t the same as material participation (defined later). Active participation is a less stringent standard than material participation. For example, you may be treated as actively participating if you make management decisions in a significant and bona fide sense. Management decisions that count as active participation include approving new tenants, deciding on rental terms, approving expenditures, and similar decisions.