We demonstrate that half‐wavelength facet coatings of Al2O3can arrest the growth of pulsations in the output intensity of (Al,Ga)As double‐heterostructure lasers during cw aging in a 70 °C dry nitrogen ambient while also eliminating an initial mode of degradation. These concurrent effects of the coatings suggest a common origin for the aging‐induced pulsations and the initial degradation and also support a recently proposed model for the origins of pulsations.