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Praxikon

Article 6: Lawfulness of processingAI-relevant

Praxikon tracks Article 6 (Lawfulness of processing) under the GDPR, alongside the EU AI Act, citing the source for every statement.

Chapter IIIn force since 25-05-2018

What does Article 6 govern?

Article 6 determines when the processing of personal data is lawful. Paragraph 1 lists six legal bases, at least one of which must apply: consent (a), performance of a contract (b), a legal obligation (c), vital interests (d), a task in the public interest or official authority (e) and legitimate interests (f). Public authorities may not rely on legitimate interests in the performance of their tasks (paragraph 1, last subparagraph). Paragraphs 2 and 3 require that bases (c) and (e) are laid down in Union or Member State law and allow Member States to specify them further. Paragraph 4 gives the factors for assessing whether data may be used for a purpose other than the one for which they were collected.

Key term: Legal basis: one of the six conditions in paragraph 1 that makes processing lawful; without a legal basis, processing is not permitted

Directly affects:controllerprocessordata subjectmember state

Praxikon’s reading of the text and the recitals; the official text below prevails.

AI Act intersection

A valid legal basis is required for processing personal data in AI training data. AI Act Art. 10 indirectly references this GDPR requirement.

Official text

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Processing shall be lawful only if and to the extent that at least one of the following applies: (a) the data subject has given consent to the processing of his or her personal data for one or more specific purposes; (b) processing is necessary for the performance of a contract to which the data subject is party or in order to take steps at the request of the data subject prior to entering into a contract; (c) processing is necessary for compliance with a legal obligation to which the controller is subject; (d) processing is necessary in order to protect the vital interests of the data subject or of another natural person; (e) processing is necessary for the performance of a task carried out in the public interest or in the exercise of official authority vested in the controller; (f) processing is necessary for the purposes of the legitimate interests pursued by the controller or by a third party, except where such interests are overridden by the interests or fundamental rights and freedoms of the data subject which require protection of personal data, in particular where the data subject is a child. Point (f) of the first subparagraph shall not apply to processing carried out by public authorities in the performance of their tasks.
Member States may maintain or introduce more specific provisions to adapt the application of the rules of this Regulation with regard to processing for compliance with points (c) and (e) of paragraph 1 by determining more precisely specific requirements for the processing and other measures to ensure lawful and fair processing including for other specific processing situations as provided for in Chapter IX.
The basis for the processing referred to in point (c) and (e) of paragraph 1 shall be laid down by: (a) Union law; or (b) Member State law to which the controller is subject. The purpose of the processing shall be determined in that legal basis or, as regards the processing referred to in point (e) of paragraph 1, shall be necessary for the performance of a task carried out in the public interest or in the exercise of official authority vested in the controller. That legal basis may contain specific provisions to adapt the application of rules of this Regulation, inter alia: the general conditions governing the lawfulness of processing by the controller; the types of data which are subject to the processing; the data subjects concerned; the entities to, and the purposes for which, the personal data may be disclosed; the purpose limitation; storage periods; and processing operations and processing procedures, including measures to ensure lawful and fair processing such as those for other specific processing situations as provided for in Chapter IX. The Union or the Member State law shall meet an objective of public interest and be proportionate to the legitimate aim pursued.
Where the processing for a purpose other than that for which the personal data have been collected is not based on the data subject's consent or on a Union or Member State law which constitutes a necessary and proportionate measure in a democratic society to safeguard the objectives referred to in Article 23(1), the controller shall, in order to ascertain whether processing for another purpose is compatible with the purpose for which the personal data are initially collected, take into account, inter alia: (a) any link between the purposes for which the personal data have been collected and the purposes of the intended further processing; (b) the context in which the personal data have been collected, in particular regarding the relationship between data subjects and the controller; (c) the nature of the personal data, in particular whether special categories of personal data are processed, pursuant to Article 9, or whether personal data related to criminal convictions and offences are processed, pursuant to Article 10; (d) the possible consequences of the intended further processing for data subjects; (e) the existence of appropriate safeguards, which may include encryption or pseudonymisation.

Source: EUR-Lex, Regulation (EU) 2016/679. Official text, reproduced without modification.

Decision tree

Which legal basis do you have for the processing?

Choose the legal basis per processing purpose and before the processing starts. If you process special category data, you also need an exception under Article 9(2).

Question 1 · Art. 4(1) en 2

Do you process personal data: information relating to an identified or identifiable natural person?

Pseudonymised data, IP addresses and customer numbers can also be personal data.

Full diagram
  1. 1

    Do you process personal data: information relating to an identified or identifiable natural person?

    Art. 4(1) en 2

    • Yes → Question 2
    • No → Outcome A
  2. 2

    Is the processing necessary for compliance with a legal obligation to which you are subject, laid down in Union law or Member State law?

    Art. 6(1)(c) · Art. 6(3)

    • Yes → Outcome B
    • No → Question 3
  3. 3

    Is the processing necessary for the performance of a task carried out in the public interest or in the exercise of official authority vested in you by law?

    Art. 6(1)(e) · Art. 6(3)

    • Yes → Outcome C
    • No → Question 4
  4. 4

    Is the processing necessary for the performance of a contract to which the data subject is party, or to take steps at the data subject’s request prior to entering into a contract?

    Art. 6(1)(b)

    • Yes → Outcome D
    • No → Question 5
  5. 5

    Is the processing necessary to protect the vital interests of the data subject or of another natural person, such as in a medical emergency?

    Art. 6(1)(d)

    • Yes → Outcome E
    • No → Question 6
  6. 6

    Are you a public authority carrying out this processing in the performance of its tasks?

    Art. 6(1), second subparagraph

    • Yes → Question 10
    • No → Question 7
  7. 7

    Step 1: do you or a third party pursue a legitimate interest that is lawful, clearly articulated and actually present?

    Art. 6(1)(f)

    • Yes → Question 8
    • No → Question 10
  8. 8

    Step 2: is the processing necessary for that interest, meaning you cannot reasonably achieve the purpose with less or less intrusive processing?

    Art. 6(1)(f)

    • Yes → Question 9
    • No → Question 10
  9. 9

    Step 3: are the interests and fundamental rights of the data subjects not overriding, taking into account their reasonable expectations, the nature of the data and extra protection for children?

    Art. 6(1)(f) · overweging 47

    • Yes, their interests do not override → Outcome F
    • No, or in doubt → Question 10
  10. 10

    Can you obtain freely given, specific, informed and unambiguous consent through a clear affirmative act, which you can demonstrate and which is as easy to withdraw as to give?

    Art. 6(1)(a) · art. 7 · Art. 4(11)

    • Yes → Outcome G
    • No → Outcome H

Outcome A · Does not apply

The GDPR does not apply

Without personal data you need no legal basis. Note: data that can be linked to a person with reasonable means, including via someone else, do count as personal data.

Art. 4(1) · overweging 26

Outcome B · Applies

Legal basis: legal obligation

You process under Article 6(1)(c). The purpose follows from the law itself. Do not process more than the obligation requires and do not keep data longer than the law prescribes.

Art. 6(1)(c) · Art. 6(3)

Outcome C · Applies

Legal basis: public task or official authority

You process under Article 6(1)(e). The task must have a basis in Union or Member State law, and the processing must be necessary and proportionate. Data subjects may object (Article 21).

Art. 6(1)(e) · Art. 6(3) · art. 21

Outcome D · Applies

Legal basis: performance of a contract

You process under Article 6(1)(b), but only what is objectively necessary for the contract. For extra purposes, such as marketing or product development, you need another legal basis.

Art. 6(1)(b)

Outcome E · Applies

Legal basis: vital interests

You process under Article 6(1)(d). This basis is meant for situations where someone's life or health is at stake, such as a medical emergency or a humanitarian emergency. Where it concerns the vital interest of a person other than the data subject, you should in principle rely on it only where the processing cannot manifestly be based on another legal basis (recital 46).

Art. 6(1)(d) · overweging 46

Outcome F · Applies

Legal basis: legitimate interests

You process under Article 6(1)(f). Record the three steps in writing and state the interest in your privacy notice. Data subjects have a right to object; for direct marketing that right is absolute.

Art. 6(1)(f) · Art. 13(1)(d) · art. 21

Outcome G · Applies

Legal basis: consent

You process under Article 6(1)(a). You must be able to demonstrate consent, a request for consent must be distinguishable from other matters, and withdrawal must always be possible. After withdrawal the processing for that purpose stops.

Art. 6(1)(a) · art. 7 · Art. 4(11)

Outcome H · Prohibited

No legal basis: you may not process

Without one of the six legal bases the processing is unlawful. Adjust the purpose or design, limit the data, or seek a basis in law.

Art. 6(1) · Art. 5(1)(a)

A decision tree simplifies. If you are unsure at a question, read the provision or have it assessed. Checked against the legal text on 1 October 2026.

What does this mean for you?

Controller

Before each processing operation, decide which legal basis in paragraph 1 you rely on and record it. If you choose legitimate interests (paragraph 1(f)), you must weigh your interest against the interests and fundamental rights of the data subject, with extra weight where a child is involved; recital 47 names the reasonable expectations of the data subject as the yardstick. If you want to use data for a new purpose, for example to train an AI model, you run the compatibility test of paragraph 4, unless you have fresh consent or a legal provision that allows it.

Processor

The legal basis belongs to the controller; as a processor you cannot choose a legal basis yourself. If you use the data for a purpose of your own, you are no longer a processor for that part and need your own legal basis under paragraph 1.

Data Protection Officer

Check that a legal basis is recorded for every processing operation and that it fits the situation: recital 43 warns that consent is not a valid basis where there is a clear imbalance, for example between a public authority and a citizen. Guard the compatibility test of paragraph 4 whenever someone proposes using data for a different purpose.

Data Subject

An organisation may process your data only if one of the six legal bases in paragraph 1 applies. If it relies on legitimate interests, your interests and fundamental rights must not override that interest (paragraph 1(f)). When data are used for another purpose, recital 50 says the organisation must inform you about that purpose and about your rights, including the right to object.

Compliance checklist

Related recitals

(40)

In order for processing to be lawful, personal data should be processed on the basis of the consent of the data subject concerned or some other legitimate basis, laid down by law, either in this Regul...

(41)

Where this Regulation refers to a legal basis or a legislative measure, this does not necessarily require a legislative act adopted by a parliament, without prejudice to requirements pursuant to the c...

(42)

Where processing is based on the data subject's consent, the controller should be able to demonstrate that the data subject has given consent to the processing operation. In particular in the context ...

(43)

In order to ensure that consent is freely given, consent should not provide a valid legal ground for the processing of personal data in a specific case where there is a clear imbalance between the dat...

(44)

Processing should be lawful where it is necessary in the context of a contract or the intention to enter into a contract....

(45)

Where processing is carried out in accordance with a legal obligation to which the controller is subject or where processing is necessary for the performance of a task carried out in the public intere...

(46)

The processing of personal data should also be regarded to be lawful where it is necessary to protect an interest which is essential for the life of the data subject or that of another natural person....

(47)

The legitimate interests of a controller, including those of a controller to which the personal data may be disclosed, or of a third party, may provide a legal basis for processing, provided that the ...

(48)

Controllers that are part of a group of undertakings or institutions affiliated to a central body may have a legitimate interest in transmitting personal data within the group of undertakings for inte...

(49)

The processing of personal data to the extent strictly necessary and proportionate for the purposes of ensuring network and information security, i.e. the ability of a network or an information system...

(50)

The processing of personal data for purposes other than those for which the personal data were initially collected should be allowed only where the processing is compatible with the purposes for which...

Cross-references

More case law, guidelines and fines

In addition to the overview at the bottom of this page: rulings, guidelines and fines that interpret or apply this article, newest first. Each item was checked against the official source.

Case law (20)

  • 18 June 2026 · C-484/24 · CJEU
    NTH Haustechnik

    A court using evidence containing personal data processes it under a legal obligation, provided clear national case law sets the conditions. Unlawfully obtained evidence is not automatically excluded, but before disclosing it further the court must limit the data to what is necessary.

  • 13 November 2025 · C-654/23 · CJEUePrivacy Directive
    Inteligo Media

    Using an email address for a newsletter within the soft opt-in of the ePrivacy Directive does not also require a legal basis under Article 6 of the GDPR.

  • 19 December 2024 · C-65/23 · CJEU
    MK v K GmbH

    A collective or works agreement on employee data must also comply with Articles 5, 6 and 9 of the GDPR, and courts fully review its necessity.

  • 7 March 2024 · C-740/22 · CJEU
    Endemol Shine Finland

    Orally disclosing information about criminal proceedings is processing if the information is or will be in a filing system. Such data may not be disclosed to anyone without the requester showing a specific interest.

  • 21 December 2023 · C-667/21 · CJEU
    Krankenversicherung Nordrhein

    Processing health data under an exception in Article 9(2) also requires a legal basis under Article 6. Compensation has a compensatory, not a punitive, function.

Show 15 more
  • 7 December 2023 · C-26/22, C-64/22 · CJEU
    SCHUFA (debt discharge)

    A credit agency may not keep data on a debt discharge longer than the public register does. A supervisory authority's decision on a complaint is subject to full judicial review.

  • 9 November 2023 · C-319/22 · CJEU
    Gesamtverband Autoteile-Handel

    A vehicle identification number is personal data for anyone who reasonably has the means to link it to the keeper. Manufacturers have a legal obligation to make these numbers available to independent repairers.

  • 30 March 2023 · C-34/21 · CJEU
    Hauptpersonalrat

    National rules on employee data are only more specific rules under Article 88 if they meet the requirements of paragraph 2. Otherwise they must be disregarded, unless they form a legal basis under Article 6(3).

  • 2 March 2023 · C-268/21 · CJEU
    Norra Stockholm Bygg

    The GDPR also applies where a civil court orders a staff register to be produced as evidence. The court must weigh the interests of the data subjects and apply data minimisation, for instance through pseudonymisation.

  • 20 October 2022 · C-77/21 · CJEU
    Digi

    Copying customer data into a test database can be compatible further processing, but the data may not stay there longer than needed for testing and fixing errors.

  • 1 August 2022 · C-184/20 · CJEU
    OT v Vyriausioji tarnybinės etikos komisija

    Data that indirectly reveal sensitive information, such as a partner's name revealing sexual orientation, fall under Article 9. Publishing declarations of interests online went further than necessary.

  • 22 June 2021 · C-439/19 · CJEU
    Latvijas Republikas Saeima

    Penalty points for traffic offences are criminal offence data. A law that makes them available to anyone without a specific interest, or passes them to businesses for re-use, breaches the GDPR.

  • 11 December 2019 · C-708/18 · CJEUDirective 95/46
    TK v Asociaţia de Proprietari

    CCTV in the common areas of an apartment building can rely on legitimate interests without consent, provided the conditions of that basis are met.

  • 17 October 2019 · 1874/13, 8567/13 · ECtHRECHR
    López Ribalda and Others v. Spain (Grand Chamber)

    The Grand Chamber finds no violation of Article 8 ECHR in covert video surveillance of cashiers, given the reasonable suspicion of serious theft and the limited duration and scope.

  • 29 July 2019 · C-40/17 · CJEUDirective 95/46
    Fashion ID

    A website embedding a Facebook button is a joint controller, but only for collecting and transmitting visitor data. Consumer associations may bring proceedings on behalf of data subjects.

  • 5 September 2017 · 61496/08 · ECtHRECHR
    Bărbulescu v. Romania (Grand Chamber)

    The Grand Chamber finds a violation of Article 8 ECHR in the reading of an employee's messages. National courts must check, among other things, whether prior notice was given, whether there was a legitimate reason and whether less intrusive means were available.

  • 4 May 2017 · C-13/16 · CJEUDirective 95/46
    Rīgas satiksme

    The legitimate interests basis does not oblige disclosure of data to a third party who wants to bring a damages claim, but does not preclude such disclosure under national law. The Court set out the three cumulative conditions for that basis.

  • 19 October 2016 · C-582/14 · CJEUDirective 95/46
    Breyer

    A dynamic IP address is personal data for a website operator that has legal means to have the user identified through the internet service provider. National law may not exclude the legitimate interests basis in advance.

  • 24 November 2011 · C-468/10 · CJEUDirective 95/46
    ASNEF

    Member States may not add extra conditions to the legitimate interests basis, such as requiring that the data come from public sources. The provision has direct effect.

  • 16 December 2008 · C-524/06 · CJEUDirective 95/46
    Huber

    Necessity is an autonomous concept of EU law. A central register of foreign EU citizens is only necessary if it contains just the data required and makes applying the law more effective.

Guidelines (12)

Show 7 more

Fines (9)

  • 22 October 2024 · Data Protection Commission (Ireland)€310,000,000
    LinkedIn: behavioural analysis and targeted advertising

    LinkedIn used members' data for behavioural analysis and targeted advertising without a valid legal basis: consent was not valid, and neither legitimate interest nor contract applied. Members were also not properly informed about the legal bases relied on.

    Decision of 22 October 2024, announced on 24 October 2024. LinkedIn appealed to the Irish High Court.

  • 16 May 2024 · Dutch Data Protection Authority€30,500,000
    Clearview AI: illegal database of face prints

    Clearview scraped billions of photos from the internet and turned faces into biometric codes, without a legal basis and in breach of the ban on processing biometric data. It did not inform people, ignored access requests and had no representative in the EU.

    Decision of 16 May 2024, announced on 3 September 2024. Clearview did not object, so the fine is final. The AP imposed no separate fine for the missing EU representative (Article 27).

  • 31 December 2022 · Data Protection Commission (Ireland)€390,000,000
    Meta: contract as legal basis for behavioural advertising

    Meta relied on its terms of service as the legal basis for behavioural advertising on Facebook and Instagram, which the binding EDPB decision held was not a valid basis. Users were also not clearly told which legal basis applied to which processing.

    Two decisions of 31 December 2022 (EUR 210 million for Facebook, EUR 180 million for Instagram), announced on 4 January 2023. Meta announced it would appeal both the substance and the fines.

  • 2 September 2022 · Data Protection Commission (Ireland)€405,000,000
    Instagram: children's data public by default

    Children aged 13 to 17 could run business accounts that published their email address or phone number, and children's personal accounts were public by default. At the EDPB's direction, an infringement of the legal basis for processing was also found.

    Decision of 2 September 2022, announced on 15 September 2022. Meta appealed to the Irish High Court.

  • 25 November 2021 · Dutch Data Protection Authority€2,750,000
    Tax Administration: nationality in childcare benefits

    For years the Benefits department unlawfully kept the dual nationality of Dutch citizens and used applicants' nationality in a risk model and in fraud detection for childcare benefits, although this was not necessary. The processing was unlawful and, being discriminatory, also unfair.

    Decision of 25 November 2021, announced on 7 December 2021. The Tax Administration said it would not object.

Show 4 more
  • 15 July 2021 · CNPD (Luxembourg)€746,000,000
    Amazon: targeted advertising without a valid legal basis

    Amazon processed personal data for interest-based advertising on the basis of legitimate interest, which was not a valid legal basis. It also fell short on informing users and on honouring rights such as access, rectification and erasure.

    The administrative tribunal upheld the fine on 18 March 2025. On appeal, the Administrative Court annulled the decision on 12 March 2026 and sent the case back to the CNPD, because the CNPD had not assessed whether Amazon acted intentionally or negligently and had not weighed which corrective measure was most appropriate. The core findings of infringement were confirmed; the Article 21 complaints were held to fall outside the scope of the inquiry.

  • 1 October 2020 · HmbBfDI (Hamburg)€35,258,708
    H&M: recording employees' private lives

    For years, managers at the Nuremberg service centre kept extensive notes on the private lives of hundreds of employees, including illnesses, holidays, family problems and religion. The data were used to build profiles and inform employment decisions.

    The date is the date of the press release; according to reports H&M did not object, so the fine is final.

  • 20 December 2019 · Dutch Data Protection Authority€525,000
    KNLTB: member data provided to sponsors

    In 2018 the tennis association provided members' personal data for payment to two sponsors, who then approached the members with advertising. The AP found there was no valid legal basis and, for part of the members, an incompatible further use of the data.

    Decision of 20 December 2019, announced on 3 March 2020. After the Court of Justice judgment (C-621/22, 4 October 2024), the AP and KNLTB agreed in October 2025 to end the proceedings; the AP is reducing the fine to EUR 250,000, minus the cost of an awareness campaign. A final new fining decision was announced for June 2026 at the latest but was not found.

  • 21 January 2019 · CNIL (France)€50,000,000
    Google: transparency and consent on Android

    When creating a Google account on an Android phone, information about the processing was scattered and unclear. Consent to personalised advertising was not sufficiently informed, specific or unambiguous.

    The Conseil d'État dismissed Google's appeal on 19 June 2020; the fine is final.

Line of case lawLegitimate interests and contract

When may you process without consent?

  1. Rīgas satiksme (2017)Three cumulative conditions for legitimate interests.
  2. Fashion ID (2019)In joint control each party needs its own legitimate interest.
  3. Guidelines 2/2019 on the processing of personal data under Article 6(1)(b) GDPR in the context of the provision of online services to data subjects (2019)Necessary for the contract is an objective test.
  4. Meta Platforms v Bundeskartellamt (2023)Personalised advertising is not necessary for the contract.
  5. KNLTB (2024)A commercial interest can be legitimate, but necessity stays strict.
  6. Guidelines 1/2024 on processing of personal data based on Article 6(1)(f) GDPR (2024)The EDPB works out the three steps in guidelines.
  7. Mousse (2025)The interest must have been communicated at collection.
Line of case lawConsent and cookies

When is consent valid?

  1. Planet49 (2019)A pre-ticked box is not consent.
  2. Guidelines 05/2020 on consent under Regulation 2016/679 (2020)The EDPB: cookie walls and scrolling do not give valid consent.
  3. Orange Romania (2020)The controller must prove consent.
  4. Meta Platforms v Bundeskartellamt (2023)A dominant position does not rule out consent but weighs heavily.
  5. Opinion 08/2024 on Valid Consent in the Context of Consent or Pay Models Implemented by Large Online Platforms (2024)Pay or consent on large platforms is usually not a free choice.
  6. Inteligo Media (2025)Within the ePrivacy soft opt-in no separate GDPR basis is needed.
  7. Digital Omnibus: proposal amending the GDPR (2025)Proposal to move cookie rules into the GDPR.

Checked on 5 November 2026

Frequently asked questions

Connections

What connects to Article 6 GDPR

Themes where this returns

Where this meets the other law

The counterpart in the other law

Case law

Guidelines8 of 9

Enforcement and fines8 of 11

Legislation in motion

Analysis