The program identifies UCOs by measuring the potential control by the various shareholders of a company (the target). Control is not a simple, linear or even continuous function of the percentage of shares held. Shareholders may directly own shares in the company (direct shareholders) or have a cascading influence through one or several layers of other companies (indirect shareholders) and compete with each other for control. There may also be loops.
By virtue of providing a superior measure of control, Zeno indices, combined with recent graph theory and simulation techniques, allow the user to discriminate between the financial links that are only associated with portfolio investments and those that can potentially translate into significant control. This has major applications.