Contained in the code tax: Las Siete Partidas, of the King Don Alfonso X the wise, in 1256 to 11265. Elements: Taxable income, the commercial activity exercised by merchants that enter or leave the peoples with portadgo; Event: the sale of goods; Passive subject, the merchant or merchant who conducted the sale of goods; Active subject: the city, town or castle with portadgo who received 1/3 of the tax, and the King received 2/3; Rate: 1 ochavo of goods which are marketed. Rationale: maintenance of towers, fences and other things for all communally. Source: power of rule of the King. (Industry and Commerce tax reform proposal and conflicts. QUIÑONES MONTEALEGRE Antonio, Ed. Universidad del Rosario, Bogotá D.C., 2009, ps.82, 83.