Anti-lifting system for a canvas

An anti-lift system for a canvas (16) is described for covering an open top body (10) with centerings (14) suitable for supporting the canvas. The centerings are capable of sliding on shoes (18) above the upper edge (12) of the body between a first position in which the canvas covers the body and a second position in which the canvas is folded. In order to prevent it from accidentally lifting, the system comprises means (80, 82) that act upon a centering to anchor it to the body when it is in the first position. In order to increase the anchoring points and the reliability of the system, the means have a configuration for fixedly connecting the centering and a configuration that is modified so as to not be an obstacle for the movement of the centerings towards the second position.