The Federal Trade Commission warns "Not all multilevel marketing plans are legitimate. Some are pyramid schemes. It's best not to get involved in plans where the money you make is based primarily on the number of distributors you recruit and your sales to them, rather than on your sales to people outside the plan who intend to use the products."
The legal distinction between MLMs and traditional pyramid schemes has been characterized by many authorities as a legal fiction. Jurisdictions that retain a legal distinction between MLM pyramid businesses versus illegal pyramid schemes retain said distinction on two key distinguishing features: 1) that MLMs always encompass the sale of actual products/services, while traditional illegal pyramid schemes ordinarily do not (though sometimes they do), and 2) that climbing an MLM pyramid is overwhelmingly statistically improbable (especially to its highest participant levels) but not theoretically impossible, whereas climbing a traditional illegal pyramid scheme is both statistically and theoretically impossible.