product diversification (related/unrelated) ,ownership structure and capital structure

the paper studies of the effect the related and unrelated diversification for products and ownership structure on capital structure for a sample of 87 firms out of 19 industry listed on the tehran stock exchange during the period 2004- 2009. for to regress of models to apply of multivariate approach include panel data and cross-sectional regressions. this study adopts panel fixed effects regression models to estimate the relationship between diversification (related/unrelated), ownership structure on capital structure, while controlling for some firm-specific characteristics like size, tangibility, growth opportunities, none-debt tax shields, return of total assets and coefficient of variation.the results indicated that related diversification (rd) positively and unrelated diversification (ud) negatively and significantly, effects on capital structure. base on the definition of capital structure in this paper, firms that are undertake to unrelated diversification strategy, mainly financed by debt; whereas firms that follow related diversification strategy, increased their profitability and sale of production. therefore firms that use of the strategy (rd), minimize risk of liquidity and are likely to be mainly financed by equity. in addition, the results indicated that there was between ownership concentration and capital structure negatively and significant relation. according to the results, the firms that tend to engage in a high degree of ownership concentration, tending in have a lower level of debt in capital structure and stockholders more tend to finance by equity and thus minimize agency costs. the findings of the research also indicate that there isnot perceive significant relation between institutional stockholders and capital structure.