Due to the widespread and long-term circulation of HCoVs, and the pooling of plasma from thousands of donors for every lot, IVIGs contain significant levels of HCoV nAb levels, as was shown for example for HCoV-NL63 [5]. Whether these HCoV antibodies cross-react with, or even neutralize, the related SARS-CoV-2 has not been fully elucidated. To date, antibody binding assays have shown some cross-reactivity between different HCoVs and SARS-CoV-2; however, functional and therefore clinically more relevant virus neutralization assays have shown no or only very low levels of cross-reactive antibodies [6–8]. The question is of significant clinical relevance, as SARS-CoV-2 cross-neutralizing antibodies in IVIGs, if they were present, might afford some protection to people with immune deficiencies and may even represent a treatment option for coronavirus disease 2019 (COVID-19) patients.