The irrelevance of the MM dividend irrelevance theorem

Contrary to Miller and Modigliani [1961. Dividend policy, growth, and the valuation of shares. Journal of Business 34, 411–433], payout policy is not irrelevant and investment policy is not the sole determinant of value, even in frictionless markets. MM ask “Do companies with generous distribution policies consistently sell at a premium above those with niggardly payouts?” But MM's analysis does not address this question because the joint effect of their assumptions is to mandate 100% free cash flow payout in every period, thereby rendering “niggardly payouts” infeasible and forcing distributions to a global optimum. Irrelevance obtains, but in an economically vacuous sense because the firm's opportunity set is artificially constrained to payout policies that fully distribute free cash flow. When MM's assumptions are relaxed to allow retention, payout policy matters in exactly the same sense that investment policy does. Moreover (i) the standard Fisherian model is empirically refutable, predicting that firms will make large payouts in present value terms, (ii) only when payout policy is optimized will the present value of distributions equal the PV of project cash flows, (iii) the NPV rule for investments is not sufficient to ensure value maximization, rather an analogous rule for payout policy is also necessary, and (iv) Black's [1976. The dividend puzzle. Journal of Portfolio Management 2, 5–8] “dividend puzzle” is a non-puzzle because it is rooted in the mistaken idea that MM's irrelevance theorem applies to payout/retention decisions, which it does not.