Notes. A full description including references is provided in Sect. 2.3. r_match is the matching radius used when associating spec-z entries with the Legacy Survey DR9 catalogue. Rank gives the priority order used when determining the ‘lead’ catalogue per spec-z. N_total gives the number of spec-z within the region bounded by 126° < α(J2000) < 146.2°, −3.2° < δ(J2000) <  + 6.2° (encompassing the eFEDS X-ray footprint) which also satisfy the selection criteria listed in the text. N_lead, comp gives the number of entries in the spec-z compilation where the (sub-)survey provides the ‘best’ redshift per classification. N_{lead, X − ray} gives the number of eFEDS main sample counterparts where the (sub-)survey provides the ‘best’ redshift per classification, and the rightmost column gives the number of those which have high spectroscopic quality (NORMQ = 3). The spec-z from SDSS are subdivided into several groups: sdssv_vi and efeds_vi - these are derived from the dedicated SDSS-V and SDSS-IV eFEDS plate programs, respectively, supported by visual inspections; boss_vi and sdss_vi – archival optical spectroscopy in the eFEDS field, obtained via the BOSS or original SDSS spectrographs, and supported by visual inspections; boss_novi and sdss_novi – archival BOSS and SDSS spectroscopy without visual inspections. The data model for the spec-z compilation catalogue is described in Appendix A.3.