Notice calling a lawful strike (RDL 17/1977 + art. 28.2 CE)

Legal basis and things to bear in mind

• Legal framework: RDL 17/1977, art. 28.2 of the Constitution and STC 11/1981, which struck down parts of the decree.
• Notice: in writing and at least five calendar days before the start (art. 3.3 RDL 17/1977). In undertakings responsible for any kind of public service it is ten calendar days, and the strike must also be publicised before it begins so that users of the service know about it (art. 4).
• Strike committee: twelve people at most (art. 5). The same article requires them to be workers of the affected workplace, but STC 11/1981 held that requirement unconstitutional where the strike covers SEVERAL workplaces; the cap of twelve still stands.
• Effects on the worker: during the strike the contract is suspended and there is no right to pay (art. 6.2). The worker moves to a special Seguridad Social (Social Security) status, with the duty to pay contributions suspended for both employer and worker, and has no right to unemployment benefit or to the sickness benefit for temporary incapacity (art. 6.3).
• Replacement: while the strike lasts, the employer may not replace strikers with workers who were not linked to the undertaking when the strike was notified (art. 6.5). There is a single statutory exception: a breach of the safety and maintenance duties of art. 6.7. And note that deciding who performs those duties is no longer the employer's exclusive power, because STC 11/1981 struck that wording down.
• Replacement using the company's own resources: STC 24/2026, of 12 March (BOE-A-2026-8279, the Metro de Sevilla case), clarifies the doctrine of STC 17/2017 and holds that it infringes the right to strike to replace the service the strikers stop providing with other available resources, whether human, technical or technological, where this minimises, reduces or limits the effects of the stoppage and lets the business keep running.
• Calling the strike: STC 11/1981 struck down three requirements in art. 3: that the decision be taken in each workplace, the 75 % quorum at the representatives' meeting, and the backing of 25 % of the workforce to put it to a vote.