Article 129 establishes a General Anti-Avoidance Rule (GAAR). It applies when the Tax Authority determines that the 'main purpose' of a transaction (or a series of combined transactions) is to avoid any Omani tax liability. This rule covers transactions regardless of whether they occurred before or after the Law's effective date. It specifically targets complex arrangements where tax avoidance is achieved through the combined effect of multiple steps, including those involving company dissolutions. This gives the Authority broad power to look through the legal form of an arrangement to its underlying tax-avoidance substance.