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Abstract A ubiquitous feature of accreting black hole systems is their hard X-ray emission which is thought to be produced through Comptonization of soft photons by electrons and positrons in the vicinity of the black hole, in a region with optical depth of order unity. The origin and composition of this Comptonizing region, known as the corona, is a matter open for debate. In this paper we investigate the role of relativistic protons accelerated in black-hole magnetospheric current sheets for the pair enrichment and neutrino emission of AGN coronae. Our model has two free parameters, namely the proton plasma magnetizationσ_p, which controls the peak energy of the neutrino spectrum, and the Eddington ratio λ_X,Edd(defined as the ratio between X-ray luminosityL_Xand Eddington luminosityL_Edd), which controls the amount of energy transferred to secondary particles. For sources with λ_X,Edd≳ λ_Edd,crit(where λ_Edd,crit∼ 10^-1forσ_p= 10⁵or ∼ 10^-2forσ_p= 10⁷), proton-photon interactions andγγannihilation produce enough secondary pairs to achieve Thomson optical depthsτ_T∼ 0.1-10. In the opposite case of λ_X,Edd≲ λ_Edd,crit, the coronal pairs cannot originate only from hadronic interactions. Additionally, we find that the neutrino luminosity scales asL²_X/L_Eddfor λ_X,Edd≲ λ_Edd,crit, while it is proportional toL_Xfor higher λ_X,Eddvalues. We apply our model to four Seyfert galaxies, including NGC 1068, and discuss our results in light of recent IceCube observations.