Article 63 outlines the anti-tax avoidance measures available to the Tax Department. The Department is empowered to disregard transactions lacking a tax effect and reclassify those whose form misrepresents their substance. It may use an estimated tax assessment method if a taxpayer fails to file timely declarations or maintain accurate records. Furthermore, the Department can reallocate revenues and expenses between related parties to reflect arm's-length transactions. Losses from asset transfers between related parties are suspended until disposal to an unrelated party. The article also grants powers to adjust the tax base to counteract income splitting arrangements between related persons.