In the emerging market economies the influencing power of different strands of ownership structure and ownership concentration on the risk-adjusted returns on assets and equity, dividend yield, earnings, and cost-to income ratio of listed deposit money banks has not been thoroughly investigated. The diminutive research and equivocal findings of previous studies on this subject create grounds for further investigation. Therefore, the aim of this study is to investigate the extent to which these three constructs relate in listed deposit money banks an emerging market economy, Nigeria. Panel data multiple regressions were applied to data extracted from the annual reports from 2009 to 2020 to test the six hypotheses. The results indicate that the disaggregated ownership structure and concentrated ownership relate positively and significantly to the bank performance indices, thereby supporting convergence of owners and managers interests which reduces the agency problems and increases the financial performance of firms. The novelty of this study is the introduction of new indices for measuring performance, ownership structure and concentration which are total departure from the usual method in both emerging and developed market economies. Further research can be extended in other economies using the same computational methods.