Ultra vires doctrine in common law?

The ultra vires doctrine in common law refers to acts conducted beyond the legal power or authority of an entity, often applied in corporate law to limit the actions of corporations to those within their stated purpose as defined in their charter or articles of incorporation. If a corporation engages in activities outside its defined powers, those actions can be deemed invalid or unenforceable. This doctrine serves to protect shareholders and ensure that corporations do not overstep their legal boundaries. However, certain jurisdictions have modernized this doctrine, allowing for greater flexibility in corporate governance.