The value of control is a quantitative measure of the value of controlling the outcome of an uncertain variable. Decision analysis provides a means for calculating the value of both perfect and imperfect control. The former value, informally known as the value of wizardry, is an upper bound for the latter. Obtaining meaningful value-of-control measurements requires an awareness of important restrictions (concerning the nature of free will and the meaning of counterfactual statements) on the validity of this kind of analysis.
The number of shares outstanding in a company that is sufficient to be able to control the company. In a publicly-traded company, the control value may be 50% + 1 for ordinary decisions, or a supermajority of shares for more important decisions. If one person or company owns a control value, such shares command a higher price than other shares because each share represents a level of oversight in the company that non-control shares do not possess.
