Spatial configuration of the group member galaxies and the AGN sightlines for the four groups in our sample together with supplementary information. The left panel shows the projected position of group-member galaxies (orange dots) and the AGN sightlines along which OGrM absorption has been detected (black dots). The AGN names are labeled in black, the most important group member galaxies are labeled in gray. The right panel shows the group-member galaxies (orange dots) and the OGrM systems (green triangles) in a 3D position-velocity diagram.