Also known as the most favourable condition. It is a principle of jurisprudence according to which, by unilateral decision of the employer or by mutual agreement, more favourable conditions are established than those established by law or conventional regulations. Its legal recognition is found in article 3.1 section c) of the Workers' Statute.
Article 3.1.c ET : The rights and obligations concerning the employment relationship are regulated: c) By the will of the parties, expressed in the employment contract, its women database object being lawful and in no case may conditions be established to the detriment of the worker that are less favorable or contrary to the legal provisions and collective agreements expressed above.
The most beneficial conditions or acquired rights are produced by a habitual, regular and persistent enjoyment of them over time, provided that such repetition is indicative of the employer's willingness to recognize such benefit. The employee has the right to maintain the acquired rights.
The Christmas basket that the company gave you every December was a very common custom in our country until the economic crisis hit and most workers saw how this "gift" disappeared.

The Supreme Court has issued a ruling in which it understands that Christmas baskets are acquired rights at work and the company cannot withdraw them citing economic reasons; they can only be eliminated if agreed with the workers or their representatives.
The Supreme Court ruling of 21 April 2016 changes its doctrine since it previously understood that the delivery of the Christmas basket was an act of generosity on the part of the employer, without constituting a more beneficial condition.
Supreme Court ruling
Case history
This is a merger of two companies. The company that became the holder of labour relations did not comment on the request of the workers' representatives to maintain as acquired rights the salary and extra-salary conditions, among which was the Christmas basket.
The company committee announced that it would not be giving out the Christmas basket as it had done every December and finally, in 2013, due to the company's economic situation, the Christmas basket was eliminated.