Background/Discussion: Among investors, annual reports are used as a decision-making document to value a company. Many companies therefore use voluntary disclosure as a complement to statutory information in annual reports. Previous studies have examined what the underlying factors for voluntary disclosure are. These have among other things, resulted in factors such as size, country of origin and owner concentration, which has a significant impact on the amount of voluntary disclosure. Therefore, it is interesting to examine if there is a significant difference between the amount of voluntary disclosure in companies with controlled ownership versus management ownership. The selection is based on companies listed on the Swedish stock market Nasdaq Strockholm, Large Cap and Small Cap. Purpose: This comparative study is aiming to investigate differences in the amount of voluntary disclosure between companies with controlled ownership and management ownership. The purpose is to create a deeper understanding and increase awareness of the ownership structure's impact on voluntary information. Method: A quantitative method has been used for the study and empirical data has been collected through observations of annual reports. The collected data has then been assessed according to a valuation index designed for the study. The index has been adapted to both swedish and international regulations. The study has then used scatterplots and a t-test to measure whether or not there is a significant difference in the amount of voluntary disclosure between the two owner concentrations. Result: Based on the study's sample, there is no significant difference in the amount of voluntary disclosure between control-owned and management-controlled companies. Control-owned companies tend to report more information about accidents than managementcontrolled companies. The management-controlled companies in the study tend to report more information on marketing than control-owned companies