While driving regularly on the highway my sunroof spontaneously shattered. There were no warning signs and no visible debris on the road that could have hit it. This is the SECOND instance of this happening with this vehicle (2018 Lexus NX 300) within three years. The sudden loud sound is dangerous as it can cause someone to jerk the steering wheel. Also, if the sunroof is open, glass could rain down on the occupants of the vehicle. My sunroof was closed at the time, but my vehicle littered glass over the roadway while trying to exit safely. The dealership refuses to take responsibility for the manufacturing defects in their sunroofs.