Correlation between X-ray and radio luminosity. The dashed black line is the relationship found by Laor & Behar (2008) and the grey regions represent the 1σ, 2σ, 3σ uncertainty. The AGNs where the bulk of radio emission is due to SF are highlighted with orange squares while those where the emission is connected to the corona are surrounded by a red diamond. The dashed red line is the R_X=–4.5 traditional threshold between RL and RQ AGNs (Terashima & Wilson 2003). Six RL objects exceed the 3σ uncertainty region, but all other SUBWAYS targets follow the L_R/L_X ∼ 10^−5.5 relation. PG0947+396 (6) and PG1352+183 (4) (red diamonds in the left panel), are unresolved and satisfy the expectations for a corona-dominated spectrum at GHz frequencies. The overall trend confirms that RQQ follow the Güdel–Benz relation almost independently on their radio spectral shape (e.g. Laor & Behar 2008; Panessa & Giroletti 2013).