How is flight envelope protection implemented in Dassault Falcons?
My information on the Falcon 7x and 8x comes from Aviation Week and Flying Magazine pilot-reports.
It would appear that the Dassault FBW philosophy is very closely aligned with that of Airbus. Namely,

It employs a C* control law without speed stability;
It uses passive sidestick instead of control column;
It employs 3-axis envelope protection, complete with bank angle protection (via positive spiral stability beyond 35 deg), load factor protection, AOA protection and high speed protection;
It even has a control-by-wire backup system similar to the mechanical backup available in the A320 and A330.

The fact that it has a C* control law, which provides flight path stability and not speed stability, and that it has a passive sidestick without force feedback, the envelope protection would appear to be a must-have for certification, rather than nice-to-have. By all indications, the limitations are hard constraints that cannot be overridden by pilot inputs in Normal Law.