Originally Posted by
Kevin AA
I don't think denied boarding rules apply to overweight, only to oversold.
You might want to read section 4 of the linked DOT site in the post above yours.
Originally Posted by
BigFlyer
It was a 737 that was not entirely full. My understanding was that there was not enough fuel to carry the number of passengers that were on the flight to the destination.
Overweight and not enough fuel are not the same thing. Airplanes have max takeoff and landing weights (which might not be the same), and can also be constrained further by local conditions, such as runway length, altitude, and temperature (the latter two affecting air density).
As others have mentioned, compensation depends on where this occurred and where the airline is based. Assuming US, the DOT summary linked in post 4 above would explain what conditions require compensation. On planes with over 60 seats, bumping pax because of "safety-related aircraft weight or balance constraints" does constitute IDB. Compensation amounts are determined by how long the pax is delayed (by schedule, not actual). If they put your friend on a flight that was scheduled to arrive at the destination within one hour of the original time, no compensation is due. 1-2 hours should net 200% of the one-way fare, capped at $650, longer than two hours doubles those amounts. The time periods are different for international flights.