A labelling group (4, 5) for applying at least one label onto a respective article (11, 11a, 11b) at an application station, comprising: - a transfer element, which is adapted to transfer said label along an arc-shaped trajectory having centre on a trajectory axis and which comprises a transfer station, and can be arranged in an operative position, in which said transfer station coincides, in use, with said application station and in which said trajectory is tangent to said article travelling along an arc-shaped path having centre on a path axis; said transfer element being movable in at least one rest position, in which said trajectory is spaced from said application station; characterized in that said labelling group further comprises: - a diverting device, which can be selectively arranged in: a first configuration, in which it allows said transfer element to convey said label along at least part of said trajectory and to release said label at said transfer station; or in a second configuration, in which it prevents said transfer element either from receiving said label or from releasing said label to said transfer station; in that said diverting device is arranged, in use, in said first configuration when said transfer element is arranged, in use, in said operative position; in that said diverting device is arranged, in use, in said second configuration when said transfer element is arranged, in use, in said at least one rest position; and in that said transfer element is movable between said at least one of rest position and said operative position along a rectilinear path parallel to a direction, which is radial to said path and said trajectory and lies on a plane orthogonal to said path axis and said trajectory axis when said transfer element is arranged in said operative position. - a transfer element, which is adapted to transfer said label along an arc-shaped trajectory having centre on a trajectory axis and which comprises a transfer station, and can be arranged in an operative position, in which said transfer station coincides, in use, with said application station and in which said trajectory is tangent to said article travelling along an arc-shaped path having centre on a path axis; said transfer element being movable in at least one rest position, in which said trajectory is spaced from said application station; characterized in that said labelling group further comprises: - a diverting device, which can be selectively arranged in: a first configuration, in which it allows said transfer element to convey said label along at least part of said trajectory and to release said label at said transfer station; or in a second configuration, in which it prevents said transfer element either from receiving said label or from releasing said label to said transfer station; in that said diverting device is arranged, in use, in said first configuration when said transfer element is arranged, in use, in said operative position; in that said diverting device is arranged, in use, in said second configuration when said transfer element is arranged, in use, in said at least one rest position; and in that said transfer element is movable between said at least one of rest position and said operative position along a rectilinear path parallel to a direction, which is radial to said path and said trajectory and lies on a plane orthogonal to said path axis and said trajectory axis when said transfer element is arranged in said operative position. a first configuration, in which it allows said transfer element to convey said label along at least part of said trajectory and to release said label at said transfer station; or in a second configuration, in which it prevents said transfer element either from receiving said label or from releasing said label to said transfer station; in that said diverting device is arranged, in use, in said first configuration when said transfer element is arranged, in use, in said operative position; in that said diverting device is arranged, in use, in said second configuration when said transfer element is arranged, in use, in said at least one rest position; and in that said transfer element is movable between said at least one of rest position and said operative position along a rectilinear path parallel to a direction, which is radial to said path and said trajectory and lies on a plane orthogonal to said path axis and said trajectory axis when said transfer element is arranged in said operative position.