If you are denied boarding due on any oversold flight departing from the US, the airline must pay you compensation of up to US$1,350 in cash (see exceptions).
Your rights are governed by 14 CFR 250. (You may be entitled to additional compensation under the Montreal Convention, if applicable.)
The amount of compensation depends on the destination of your flight and the delay caused by the denial of boarding.
Denied boarding compensation must be paid immediately, at the airport where the incident takes place.