Ultra vires

('beyond the powers') is a Latin phrase used in law to describe an act that requires legal authority but is done without it. Its opposite, an act done under proper authority, is ('within the powers'). Acts that are may equivalently be termed "valid", and those that are termed "invalid".

Legal issues relating to can arise in a variety of contexts: * Companies and other legal persons sometimes have limited legal capacity to act, and attempts to engage in activities beyond their legal capacities may be . Most countries have restricted the doctrine of in relation to companies by statute. * Similarly, statutory and governmental bodies may have limits upon the acts and activities which they legally engage in. * Subordinate legislation which is purported passed without the proper legal authority may be invalid as beyond the powers of the authority which issued it. Provided by Wikipedia