Abstract: A device for positively restraining data tape cassettes within a magazine of a cassette loading assembly to prevent the cassettes from becoming dislodged from the magazine when the cassettes are not engaged within the tape drive. The device includes a spring loaded cantilever having an end section which engages a detent conventionally formed in the edge portion of the data cassette tape. When the cantilever end section is engaged in the detent, the cassette tape is securely held against a rear interior wall of the magazine. The spring loaded cantilever is pivotally mounted by a shaft to an interior side wall of the magazine. In operation, a cassette transfer system engages the tape cassette to load the cassette into the tape drive. However, prior to such engagement, a bracket mounted on the cassette transfer system contacts a load-receiving end of the cantilever opposite the end section within the cassette tape detent.