In the policy brief series linked, they do draw a distinction between TNC and ridesharing:

> Ridesharing — Ridesharing involves adding passengers to a private trip in which driver and passengers share a destination. Such an arrangement provides additional transportation options for riders while allowing drivers to fill otherwise empty seats in their vehicles. Traditional forms of ridesharing include carpooling and vanpooling. This term is sometimes used to refer to ridesourcing.

> Transportation Network Company (TNC) — A company that provides ridesourcing services.