In theory, private corporations are run for the benefit of their stockholders. Insofar as the theory is enforced in practice, it is through two different mechanisms. One is the fiduciary obligation of corporate directors, the fact that they are legally obliged to run the firm in the interest of its stockholders. How much effect that obligation has is not clear, given the obvious difficulties with having a court second guess the decisions of the firm. The second and more important mechanism is the fact that the board of directors, which has the power to hire and fire management, is itself elected by a vote of the stockholders. If holders of a majority of the shares are unhappy with how the corporation is being run, they can replace the existing board, and so the existing management, with people who will run it more nearly as they wish.



This mechanism, like democratic voting in the political arena, faces an obvious problem; the holder of a share of stock, like an individual voter, knows that his vote is very unlikely to change the outcome and so has little incentive to spend time and energy judging how well the firm is being run in order to exercise his voting power. But votes in the corporate context, unlike votes in the political context, are transferable; each is attached to a share of stock, and shares can be bought and sold. If a corporation is doing a sufficiently bad job of maximizing stockholder value, someone with the necessary assets and expertise can buy up lots of shares at a price reflecting the current performance of the corporation. Since owning lots of shares gives you lots of votes, he can then, perhaps in alliance with other large shareholders, vote out the board, replace management and, when it becomes clear to others that the firm is now doing better for its stockholders, sell his shares at a higher price and go looking for another badly run firm to buy stock in. Takeover bids generally get a bad press, possibly due to the efforts of incumbent managers who would prefer not to be replaced, but they provide people running corporations with an incentive not to deviate too far from doing what, in theory, they are supposed to do.



Some people—including a colleague of mine whose recent work inspired this essay—argue that the theory itself is wrong. Decisions made by a corporation affect not only the stockholders but other people as well, most obviously its customers and employees. Why not alter the legal rules in ways designed to give all "stakeholders," all people affected by the corporation's decisions, a voice—either by altering the legal rules to broaden the fiduciary obligation of directors or by changing the rules on how directors are chosen to give (at least) customers and employees some votes as well?



There are a number of problems with the argument; in this post I will focus on one of them.



Corporations are constrained in at least three different ways. Two of them are the legal obligations of the directors and the mechanisms for electing them. The third constraint is the market on which a corporation sells its outputs and buys its inputs. A customer who finds that the corporation is not serving his interests, that its products are more expensive or less desirable than those offered by competitors, does not have to intervene in the internal affairs of the corporation in order to solve the problem. He can simply stop buying what the corporation is selling. An employee who finds that the corporation is offering less money for a less attractive job than alternative employers can quit. Since the corporation requires customers to provide the money with which it pays dividends to its stockholders and salaries and bonuses to its management, and requires employees to produce the goods and services that it sells to those customers, it has a direct and immediate incentive to produce what customers want to buy and provide employment terms that employees are willing to accept.



Like most mechanisms, this one is imperfect. Customers are not perfectly informed about what they are getting or the alternatives, and some customers for some goods and services are to some degree locked in by previous choices. Having spent time and effort learning to use the hardware and software on which I am writing this, I would be willing to switch only if the quality went down quite a lot or the price up quite a lot, so the firms providing the hardware and software have some ability to benefit themselves at my expense without losing my business. Having accepted my current job, there would be significant costs to shifting to another—costs of learning my way around a different university, perhaps of moving to a different location. Hence my employer as well has some ability to benefit itself at my expense.



But my situation as customer and employee is very much better in this respect than my situation as a stockholder. It is true that, as a stockholder, I have the option of selling my shares of stock, which at first glance looks rather like my option as a consumer of not buying a product or as a worker of quitting a job. But the apparent similarity is an illusion.



If I choose not to spend twenty thousand dollars buying a car from Ford, Ford has one more unsold car and twenty thousand dollars less money. If I choose to sell twenty thousand dollars of Ford stock, on the other hand, the money I get is not coming at Ford's expense. Another investor has paid me the money and now owns the stock, leaving Ford itself unaffected. From the standpoint of the firm's incentives, it is as if, every time a customer wished to stop buying from a store, he was required to first find a new customer willing to take his place, or as if an employee could only quit if he provided a replacement willing to do the same job at the same pay.



The stockholder's view of the value of the stock directly affects the firm only if the firm wishes to raise capital by selling a new issue of stock. So far as existing stock is concerned, the shareholder is locked in, even if the fact is not immediately obvious. If the firm is being run in a way that fails to maximize stockholder value, he cannot escape that cost by selling his share, since the price he can sell it for will reflect the reduction in future profits and dividends, insofar as it can be estimated by other stockholders.



It follows that stockholders, unlike customers and employees, receive no direct protection from the market on which they deal with the firm. As a customer of Apple, I am to some limited degree locked in; I can switch to hardware and software from another firm, but only at a significant cost. The same is true of my situation as an employee of Santa Clara University. In both cases, I have born what are now sunk costs as a result of my initial decision to buy a product or accept a job. But as a stockholder in Apple, I am entirely locked in; all of my cost is sunk. If Steve Jobs announces tomorrow that he plans to run Apple entirely for the benefit of its employees and customers, never paying another dividend, the fact that I can respond by selling my stock provides me no protection.



It follows that the stockholder is dependent, very much more than the other stakeholders, on other mechanisms for controlling a firm to make it act in his interest. That is a strong argument in favor of the current mechanism for corporate control and the current legal rules defining the fiduciary obligation of the directors.



Indeed, it is an argument for more than that. It is an argument for strengthening stockholder control in order to provide more protection to the most vulnerable party in the network of relationships that makes up a corporation. One way of doing so would be by removing current legal barriers that make takeover bids more difficult, and so protect managers and directors from the consequences of serving their own interests at the expense of the stockholders whose interests they are supposed to be serving.

