Since there is no market for bond issuance by companies in the Iraqi market and the difficulty of borrowing, companies must resort to proprietary financing to finance their investments. However, in the framework of the literature of financial management, the type of financing used by the company sends signals to investors and therefore reflected on the market value. Therefore, the problem of the study revolves around the variables of the study (Equity financing within the framework the signal theory, price of common stock in the Iraqi market).     

The study aims to verify the impact of the capital increase through the issuance of new stock on the price of common stock in the Iraqi market for securities, The study sample included 10 companies, the number of cases increase (13) cases, as some companies have increases more than once during the study period which covered the years 2010 and 2011. to achieve this objective has been tested hypothesis of the study, the hypothesis that "There is a significant difference between the average price of the Common stock before and after the capital increase through the issuance of new common stock of the companies surveyed" .To test the hypothesis of the study data were analyzed using T-Test.

The study has reached into number of conclusions, the most important that the test results showed a difference statistically significant between the average price of common stocks before and after the capital increase, recalling the results to the lower average price of common stocks after the capital increase, and this means that the capital increase by issuing new common stocks are negative signal about the company to market Securities. The study was presented a set of recommendations, the most important that it should the boards of directors stay away as much as possible for issuing new shares, and the adoption of the principle of transparency and disclosure by companies and that will reduce the negative assessments by investors for the company's future.