Abstract
We analize the most important and rilevant interests that law operators must consider during their analisys about managers' way of taking decisions. This analisys put its attention on the relationship between companies under the control of other companies and in particular on the influence that the control may have on the result of manages' decisions. The aim of this work is to offer a clear view on the most important theory that today is the base of Courts' decisions. It criticizes this theory because it is useless to solve problems and on the other way, creates other problems due to its difficult interpretation.