Article 311 [source]

Spanish Criminal Code
English translation

The following shall be liable to a prison sentence of between six months and six years and a fine of between six and twelve months:

1. Those who, through deception or abuse of a situation of need, impose on their employees working conditions or Social Security provisions that harm, eliminate, or restrict the rights recognized by legal provisions, collective agreements, or individual contracts,

2. Those who impose illegal conditions on their employees by hiring them under arrangements outside the scope of an employment contract, or who maintain such conditions in defiance of a requirement or administrative sanction.

3. Those who simultaneously employ multiple workers without registering them with the corresponding Social Security system or, where applicable, without having obtained the corresponding work permit, provided that the number of affected workers is at least:

a) twenty-five percent, in companies or workplaces employing more than one hundred workers;

b) fifty percent, in companies or workplaces employing more than ten and no more than one hundred workers; or

c) all of them, in companies or workplaces employing more than five and no more than ten workers.

4. Those who, in the event of a transfer of business, with knowledge of the procedures described in the preceding sections, maintain the aforementioned conditions imposed by another party.

5. If the conduct described in the preceding sections is carried out with violence or intimidation, the penalties will be increased.