Having adequate, sufficient and timely information and data is very important for investors' decision making. Processing information and allocating the asset are two fundamental tasks in the securities market and the stock price is more likely to have the nature of disclosure, information effectiveness and asset allocation efficiency. Thus, in this research, the effects of large block transactions and ownership nature on the non- financial disclosure have been investigated in the corporates accepted in Tehran Stock Exchange. Research population involves the corporates accepted in Tehran Stock Exchange for a 5-year period (2010-2014) that according to research constraints and using the systematic deletion method, the data related to 133 corporates were gathered. In this study, five main hypotheses have been suggested. To analyze the desired data and test the research hypotheses, the software of Eviews has been implemented. Results indicated that the number of large block transactions and nature of ownership are effective in non-financial information disclosure at the whole and the corporates with high transactions, those with low transactions, those in a business group and those in a diverse business group but the effect and explanatory of dependent variables by the independent ones vary at each level.
