Ministerial Decision No. 55 of 2025, implementing Decree-Law No. 157 of 2024, establishes a key anti-avoidance provision in Article 101. This article grants the Tax Administration authority to disregard transactions or arrangements where a principal purpose is tax reduction, deferral, or exemption. The Administration will evaluate the arrangement's genuine commercial or economic rationale, its method of execution, and the consistency between its legal form and economic substance. This rule ensures that tax outcomes align with underlying economic reality, preventing artificial structures designed to circumvent the DMTT.