This paper investigates whether there is a difference in the investor returns of companies listed on the Johannesburg Stock Exchange. The analysis covers companies listed in the financial and industrial sectors during the period January 2002 to June 2007 and looks at overall returns, returns through share price changes and returns through dividend distributions. The purpose is to gain insight into whether ownership structure has an effect on company returns and to expand the information base that investors can draw on when assessing opportunities. In performing this research company management and ownership information has been used to categorise companies as owner-managed or non-owner managed and then share price data, dividend distributions have been used to calculate investor returns on a quarterly basis. This allowed descriptive analysis and hypothesis testing to be performed on the data to identify differences and then the statistical significance of any of these differences. The results obtained indicate that there are no statistically significant differences in the overall returns between the two groups but that differences between the two groups of companies do exist, primarily in the makeup of the returns rather than an overall difference in returns. In drawing these conclusions, it became apparent that further questions have arisen, particularly related to the reasons for the difference in nature of the returns. This begs for further investigation.