A floating caliper (2) for a disc brake comprises a first half-caliper (10), which houses a reaction piston (50), a second half-caliper (12), which houses an action piston (90) and locking means for locking the action piston (90) in a preset parking position. The reaction piston (50) is elastically yielding when the braking action acting on it exceeds a preset parking action threshold which corresponds to said parking position wherein the locking means lock the action piston (90).