Algorithmic transparency for workers is the employer’s duty to tell every new worker which algorithms make decisions about their working conditions. Where the employer uses them, it must also explain the rules they follow. The duty comes from letter k of Article 3.2 of Spain’s Royal Decree 723/2026 of 9 September. It was published in the Official State Gazette (BOE) on 15 September and has been in force since 5 October 2026. It covers any system involved in working hours, tasks, pay, promotion, place of work or dismissal. It makes no difference whether the system is artificial intelligence or a fixed-rule program. The information is given in writing before work starts and is updated whenever the system changes. The AI Act will not require anything similar until 2 December 2027, and only for high-risk AI.
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Letter k requires employers to disclose the existence of algorithmic or automated decision-making systems. Where those systems are used to decide on working conditions, the information must also cover their guidelines, criteria and operating rules. The text is in Royal Decree 723/2026 (in Spanish), which transposes Directive (EU) 2019/1152 on transparent and predictable working conditions. It replaces Royal Decree 1659/1998, which had governed this information for almost three decades.
The article lists six areas of decision introduced by the words «such as», so the list is open.
The common thread is that the system plays a part in setting or changing a working condition. An algorithm that allocates weekend shifts is covered. One that only sorts the emails in an inbox is not, because it decides nothing about the employment relationship.
Candidate selection is not on the list, because this information is given to people who have already been hired. Recruitment algorithms have their own rules under the Spanish Workers’ Statute (Estatuto de los Trabajadores) and the GDPR.
The Royal Decree does not spell out what guidelines, criteria and operating rules are. The most complete reference is the guide Algorithmic information in the workplace (in Spanish), published by the Spanish Ministry of Labour in May 2022. It was written for Article 64.4(d) of the Workers’ Statute and for the GDPR, not for this decree, but it describes the same kind of information. Of the fifteen items it lists, these are the most useful for drafting each worker’s document.
In practice, the information is only useful if the worker can understand it. Take a bonus that weights on-time deliveries at 60 % and customer ratings at 40 %. The worker must be able to read it in exactly those terms, and know that a manager reviews every calculation before it is paid.
The Royal Decree does not define an algorithmic or automated decision-making system. Nor does it require the system to be artificial intelligence or to decide without human involvement. The 2022 guide already took the view, for the Workers’ Statute, that the right to information arises even when the algorithm merely supports the decision. The line is drawn by the use, not by the tool.
| Use | Covered by letter k? | Why |
|---|---|---|
| Software that allocates shifts according to demand and availability | Yes | It decides how working time is distributed |
| Bonus calculated with a formula of performance indicators | Yes | It sets part of the pay |
| Platform that scores performance and feeds into promotions | Yes | It plays a part in career progression, even if a person takes the final decision |
| App that assigns orders or routes among staff | Yes | It allocates tasks |
| Payroll software that applies the agreed salary and the collective agreement | Probably not | It executes a condition already set, it does not determine it |
| Generative AI used to draft emails or summarise documents | No | It plays no part in decisions on working conditions |
| Generative AI used to rank candidates for a promotion | Yes | It is a general-purpose tool, but here it decides on career progression |
Borderline cases are settled by asking whether the system’s output carries weight in a decision about the person. If it does, the prudent course is to disclose. Disclosing too much costs a paragraph in the contract. Disclosing too little is an infringement.
The information is given before the employment relationship begins, under Article 7.1. It can be included in the written employment contract itself. If it is not, the employer provides it in one or more separate documents, on paper or in electronic form. Electronic form is valid if the worker can access, store and print it. The employer must also keep proof that it was sent or received, under Article 6.
| Situation | Deadline | Legal basis |
|---|---|---|
| New hire from 5 October 2026 | Before the employment relationship begins | Article 7.1 |
| Change in the system or its rules | As soon as possible and, at the latest, on the day the change takes effect | Articles 5 and 7.3 |
| Worker hired before 5 October | Thirty working days from the request, unless the worker already has it | Sole transitional provision, paragraph 1 |
| Change after 5 October to an earlier contract | At the latest, on the day the change takes effect | Sole transitional provision, paragraph 2 |
| Employment relationship of four weeks or less | Does not apply | Article 2.2 |
The Spanish Public Employment Service (SEPE) published on 1 October 2026 the model information document (in Spanish) required by the first additional provision. It is a seven-page form, also available in Catalan, Galician, Basque and Valencian. Its section I is headed “existence of algorithmic or automated decision-making systems related to the setting, variation or modification of working conditions” and leaves a free-text box. The heading only names the existence of the system. Letter k also requires its guidelines, criteria and rules when the system decides on working conditions, so the box has to include them or refer to an annex signed with the document. Using the model is optional, and not using it does not exempt the employer from the duty to inform, according to the first additional provision itself.
This case is fictitious. Rutalia Logística, S.L. runs last-mile parcel delivery in Madrid with 140 couriers on its payroll. One piece of software allocates shifts every week according to forecast demand and declared availability. Another calculates a monthly bonus with two indicators, on-time deliveries and recipients’ ratings.
On 13 October 2026 Rutalia takes on twelve couriers. Before their first day it gives them the contract with an annex on the two systems. The annex explains what data they use, how much each indicator weighs and who reviews the results. For the Christmas peak it also hires eight people for three weeks. The obligation does not reach them, because their employment lasts no more than four weeks.
On 20 October, a courier hired in 2025 asks for the information in writing. Rutalia has thirty working days to provide it. In November, the bonus software provider changes the weighting and gives more weight to recipients’ ratings. That change means informing all affected staff again, at the latest on the day it applies. As Rutalia has a works council, the change also triggers the council’s right to information under Article 64.4(d) of the Workers’ Statute. If the provider gives no advance notice, Rutalia is in breach without knowing it.
Royal Decree 723/2026 is not the first Spanish rule requiring employers to explain workplace algorithms. What is new is that it requires the information for every worker, for any system and before the first day. Until now there were two layers, and the AI Act will add another in 2027.
| Rule | Who receives the information | Which systems | Since when |
|---|---|---|---|
| Spanish Workers’ Statute, Article 64.4(d) | The works council | Algorithms or AI systems affecting working conditions and access to and retention of employment, including profiling | Since 2021 |
| GDPR, Articles 13, 14 and 22 | Each person concerned | Decisions based solely on automated processing, including profiling | Since May 2018 |
| Royal Decree 723/2026, Article 3.2(k) | Each worker | Any algorithmic or automated system that decides on their working conditions | Since 5 October 2026 |
| AI Act, Articles 26.7 and 26.11 | Workers’ representatives, affected staff and the people decisions are made about | High-risk AI systems, including the employment systems in Annex III | From 2 December 2027 |
The preamble of the Royal Decree makes the link with the Artificial Intelligence Act explicit. It states that letter k «is based on Articles 2.11, 26.7, 26.11 and 86 of Regulation (EU) 2024/1689». Article 2.11 allows Member States to keep or introduce rules that are more favourable to workers on the use of AI by employers. Spain has used that leeway to bring forward individual information by more than a year. It has also extended it to systems the AI Act does not treat as high-risk, or that are not AI at all.
Article 86 of the AI Act recognises a different right, the right to an explanation of a specific decision taken with a high-risk system. Letter k does not go that far. It requires the rules to be described before they are applied, not each result to be justified afterwards. The AI Act in employment, including recruitment, is covered in our AI Act compliance guide for businesses.
The duty to inform lies with the employer, even if someone else developed the algorithm. In many startups and scaleups, shifts, appraisals or incentives run on third-party software. The employer does not know by itself the rules it has to explain, and only the provider can supply that information.
The contract with the provider must enable the employer to comply with Articles 3.2(k) and 7.3. It should include at least these commitments.
These clauses fit in the SaaS or licence agreement and in the service level agreement, as part of technology contracting with each provider. Negotiating them at signature costs less than at renewal, and we explain how to draft them in our guide on algorithmic transparency clauses with your software vendor.
Disclosing guidelines, criteria and rules does not mean handing over the source code. The Ministry of Labour’s 2022 guide says so expressly for the Workers’ Statute and the GDPR. Letter k uses equivalent wording, which points to how the system works and not to how it is programmed. The provider can protect its code and training data as trade secrets. What the contract must avoid is leaving the employer without an understandable explanation of how the system decides.
No. Royal Decree 723/2026 requires employers to disclose the existence of the system and its guidelines, criteria and operating rules, not its programming. The Spanish Ministry of Labour’s May 2022 guide already made clear that the duty of algorithmic information does not require handing over the source code. It is enough to explain what data the system uses, how it weights them, what it decides and what human involvement there is.
It is a minor infringement. Article 6.4 of the Spanish Law on Social Order Infringements and Penalties (LISOS) penalises failing to inform workers in writing of the essential elements of the contract. The terms and deadlines are those set by regulation, which since 5 October is Royal Decree 723/2026. The fine ranges from 70 to 750 euros, depending on the degree. The Royal Decree does not create penalties of its own. What it does is add algorithms to the mandatory information.
Yes, at their request. Anyone already working for the company on 5 October 2026 can ask for the information. The employer has thirty working days to provide it, unless the worker already has it. In addition, any change to the system after that date must be communicated to the affected workers at the latest on the day it takes effect.
Only if they are used to decide on working conditions. Drafting emails, summarising documents or preparing presentations with generative AI does not trigger letter k. Using it to score candidates for a promotion, allocate tasks or propose dismissals does. In those cases it plays a part in decisions on progression, tasks or termination of the contract. What matters is the use, not the tool.
It does not apply to employment relationships of four weeks or less. Article 2.2 of Royal Decree 723/2026 limits the chapter on the essential elements of the contract to relationships lasting more than four weeks. Letter k is in that chapter. A three-week cover contract is outside it and a five-week contract is inside.
5 October changes little for employers that already documented their algorithms for the works council. For those that had never considered it, it changes a great deal. The real work is to map which systems decide on staff and to obtain from the provider an explanation that can be passed on. Then a process is needed to give notice of every change. That same inventory will be useful in December 2027, when the AI Act brings its own obligations for high-risk employment systems. At Innovatech we help technology companies organise their use of algorithms and AI as part of our AI legal advisory service. Write to us and we will give you a free initial assessment.
Marta Suárez-Mansilla is Managing Partner of Innovatech Legal and a Spanish lawyer (abogada), Madrid Bar (ICAM), working in technology law. She completed Harvard Law School's Copyright course and BerkeleyX's Blockchain programme, and has advised technology companies for more than eight years.
