Introduction
Corporate finance theory has not yet determined the consequences of fragmenting a firm’s probability distribution of future market value into classes of securities.
Modigliani- Miller (1958) demonstrate that when production-investment decisions are held fixed. the value of a firm is invariant to the composition of its capital structure given a perfect capital market (frictionless and perfectly competitive) and no taxes.
Fama-Miller (1972. pp. 167-170) further demonstrate that under the added condition of complete protective covenants or ‘me-first rules’ the values of a firm’s individual securities are invariant to capital structure changes. However, the firm value and security value invariance propositions can fail under corporate and personal taxation (or bankruptcy costs) and under incomplete protective covenants, respectively, In short, various currently held theories make very different predictions as to the relationships between capital structure and the valuation of the firm and its individual securities.