A pressure regulating valve for activating a clutch in a motor vehicle automatic transmission, having a housing having a first transverse opening which acts as a fluid inlet, and a second transverse opening which acts at least temporarily as a fluid outlet, the two transverse openings being spaced axially from one another, and having a valve slide guided in the housing, the valve slide including an axially extending recess in its circumferential surface, the recess fluidically connecting the two transverse openings to one another in a first axial position of the valve slide and separating them from one another in a second axial position, in the circumferential surface of the valve slide the recess having a face having an undercut at its end closest to the second transverse opening.