The criterion “can be considered representative” means that a collective agreement must be the highest and most representative for the qualification of the largest and even the most representative in the field of employment concerned. If, in a given area of employment, there is more than one agreement with national coverage, the largest is chosen among them by counting the number of workers entering its scope, and this most important agreement should normally be representative, since at least 50% of all workers in the field of employment concerned fall within its scope on the basis of normal rules of applicability. Today, a special board of directors to confirm the applicability of Erga Omnes confirms which collective agreements have such applicability. Its decisions may be appealed to the labour tribunal. A collective agreement is mandatory in two situations: although it may seem like a simple task, it may cast doubt on what will happen to companies that have more than one activity. In this case, and in accordance with the decision of the Supreme Court of Madrid in a case of 20 March 2013 which supports the previous statements of the Supreme Court, the applicable agreement is one dealing with the main activity of the company. The party to the collective agreement provides the contract to the ministry in paper and electronic form, since the common class collective agreement is published in the public data network. Parties to a national collective agreement disclose the contract and additional information within one month of the contract being signed. 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. In addition, an agreement on national income policy is often, but not always, reached, bringing together all trade unions, employers` organisations and the Finnish government.  A collective agreement can also be identified by the company`s NAF or EPA code. This code characterizes the main activity of the company from the French nomenclature of activities. The number assigned by INSEE (French Statistical Institute) to each company and each of its subsidiaries consists of four numbers and one letter. The provisions of the collective agreement are not included in the employment contract. Workers have the freedom to negotiate more favourable contractual terms with their employer individually than the collective agreement provides. […] The article aims to establish the similarities and differences between collective agreements in Spain, namely that of the procedure for substantial modification of collective work […] Some criteria have been defined in the legislation and jurisprudence relating to the applicability of Erga omnes. Not all collective agreements with national coverage are necessarily eligible; It is estimated that just over half of them meet the required criteria, i.e. that the agreement in question is an agreement which (1) has national coverage in a given industry, i.e. in the area of employment concerned (2), and which can be considered representative (3). In addition, an employer who is a party to a national collective agreement must provide the ministry with information about its employee members about the collective agreements that apply to their labour relations.
The collective agreement consists of a main text applicable to all workers and several additional texts (annexs, amendments, etc.) which apply in particular to certain categories of workers. The appendices can also be used to address certain points that are not addressed in the main text. Under the Labour Contacts Act, employers should at least comply with the provisions of a national collective agreement considered representative in the sector concerned (a general collective agreement).