Eptiopes of 7 unique antibodies produced by two complementary in vivo platforms utilizing a common light chain, in a chicken (OmniClic) or rat (OmniFlic) host species on NKp46 were analysed using HDX-MS. NKp46 was used as a model target antigen due to its use in emerging Natural Killer (NK) immune engagers that are being explored clinically as potentially safer alternatives to traditional CD3-based T cell engagers. We were able to successfully identify epitopes and map conformational changes of these antibodies validating our eptiope binning results from SPR.