Abstract: Apparatus for opening signatures comprises a conveyor having a concave section onto which, in use, the signatures to be opened are deposited. Above this concave section of the conveyor there is disposed a series of rotating suckers mounted on a movable frame which is joined to a mechanism for displacing it with a reciprocating arcuate movement which follows the curve of the concave section of the conveyor. The rotating suckers are carried on bars mounted eccentrically and rotatably on associated suction heads. These bars are hollow and communicate, through a duct, with a suction source, the communication being controlled by a solenoid valve. Each of the said eccentric bars is driven to rotate by a spindle to which is rigidly connected a sprocket engaged by a slidable chain which acts as a rack.