X-ray luminosity and stellar mass relations. Left panel: Red points show the distribution of 12 protocluster members (including the Spiderweb Galaxy but excluding the two Compton-thick candidates) in the soft-band, intrinsic luminosity and stellar mass plane. Blue points are obtained stacking the protocluster members without X-ray detection in bins of stellar mass. We note that stacked L_X values should be considered upper limits, because, despite the formal positive detection, all the stacked values are consistent with noise within 1 or 1.5 σ. Right panel: Same as the left panel but in the rest-frame hard band.