Unlike such restrictions, the law also provides for certain binding elements that a collective agreement must contain (Article 23, paragraph 1): the identity of the signatory parties, the extent and scope of their application, and the day they are signed. In addition, explicit pay levels for all occupations and categories need to be included in the pay scales (Article 23, paragraph 2). Portuguese law distinguishes three types of collective agreements according to the nature of the signatories on the employer side (Article 2, Collective Labour Relations Act): association agreements negotiated by employers` organisations; multi-employer agreements negotiated by a number of employers who, whether or not they are members of employer organizations, do not act through any association to negotiate the agreement in question; Agreements concluded at the company level by a single employer. This distinction is used by law to resolve specific conflicts between collective agreements (see also collective bargaining: level of bargaining, instruments of collective labour regulation). Another legal distinction, based on the different nature of the scope of collective agreements, is defined by horizontal and vertical agreements (see below). Disability both employers and employees, whether individually or represented by trade unions and employers` organizations, have the right to take action in labour courts to request all the clauses of collective labour regulatory agreements that they consider invalid (Article 43, Collective Work Act). Continuity of the Effects of Collective Agreements The normative effect of collective agreements means that their provisions automatically replace provisions in individual employment contracts that are less favourable to workers (Article 14 of the Employment Contracts Act). The content of a new agreement may deteriorate more favourable conditions if these conditions have been included in individual contracts resulting from a previous agreement, replaced by the new agreement (which is now applicable and introduced), provided that the new agreement contains a clause expressly stipulating that it is generally more favourable to workers (i.e. the “pejus derogation” under Article 15 of the Act). The provisions of collective agreements are therefore not a substitute for the provisions of certain contracts if they have been agreed directly between the parties to the individual contract and are more favourable to the worker.
In other words, the acquired rights of workers on better terms of employment should not, in principle, be affected by a collective agreement, unless they were acquired on the basis of an earlier agreement, which was replaced by a subsequent agreement that dissolved it and which expressly contained a general clause of greater favour. If this is the case, the “conglobao” principle chosen by law as a criterion of greater ease means that one or the other particular aspect of the general conditions of employees can be aggravated (a situation characterized as infringement of acquired rights by derogation from a previous agreement). In the same article, the law also excludes the possibility of abolishing compulsory legislation or abolishing a certain type of supplementary social benefits. See also the arbitration award. Workers are not required to join a union in a given workplace. Nevertheless, most industries, with an average union training of 70%, are subject to a collective agreement. An agreement does not prohibit higher wages and better benefits, but sets a legal minimum, much like a minimum wage.