Written by Juliette Poelman
Published on 13 July 2026
Short History
A previous publication discussed the DES-daughters case, which made an important contribution to the development of Dutch liability law and to the creation of the WCAM (“Wet Collectieve Afwikkeling Massaschade”) and later the WAMCA (“Wet Afwikkeling Massaschade in Collectieve Acties”) (English: Dutch Act on Redress of Mass Damages in a Collective Action). In 2005, the WCAM came into force1. More information on this can be found in our previous publication here. This law has fairly recently evolved into the WAMCA, which came into force on 1 January 20202.
The WAMCA allows for the collective settlement of mass damages. In cases of mass damage, the damage affects a large number of individuals and is caused by one event or several similar events. The DES-daughters case3 illustrated the need for an option for collective settlement of mass damages. Collective settlement in fact comes with significant advantages. Individuals who have suffered damages can jointly litigate, which means that litigation costs can be shared. A lot of time can also be saved if one large case is pending instead of several proceedings side by side. Parties get clarity all at once thanks to the WAMCA and endless litigation is avoided. In short, the WAMCA makes claiming damages in certain circumstances more efficient and cheaper.
Volkswagen, Tiktok , Google, Amazon, Salesforce, Allergan, Airbus, GGD and others
Named companies have in common that they became involved in WAMCA proceedings. This register, as of 29 November 2023, has 13 completed cases and more than 65 pending cases, against, among others: the State, Twitter, KLM, Vattenfall, Oracle, Airbus, Apple, Peugeot, Citroën, Airbnb, Wibra, Willem-Alexander, Mercedes, Ziggo, XS4all, KPN, Meta, municipality of Amsterdam and the NZA.
Outlines of the WAMCA
If a case lends itself to WAMCA proceedings, an exclusive interest organisation is appointed. This exclusive interest organisation has the responsibility to file a claim for damages in the Dutch courts for and on behalf of the group of interested parties in the collective action.
Procedure
Step by step, a WAMCA procedure is structured as follows:
- Instituting a claim
- Review of admissibility criteria of claim
- Appointment of exclusive advocate (EB)
- Opt-out possibility
- Substantive hearing at court
- Attempted settlement and second opt-out possibility
- Court decision
Initiation of an action by exclusive interest representative
If several collective actions are initiated regarding the same event and the subsequent actions are entered in the central register on time, the court must appoint an exclusive representative (“EB”). This EB can bring a claim on behalf of its constituents and will be in charge of the proceedings. The EB represents the interests of all injured parties: thus also the interests of injured parties who are affiliated with another interest group4. The EB is selected on the basis of a number of criteria. These criteria can be found in Section 1018e(1)(a) to (d) of the Dutch Civil Code. The EB is required to look after the interests of its constituents pursuant to its articles of association and that these interests are sufficiently safeguarded. Furthermore, the EB must have a supervisory body, an internet page, sufficient experience and relevant expertise5. These requirements ensure that the EB is sufficiently able to represent the other stakeholders and claim compensation on their behalf. The EB should also meet the representativeness requirement: it should have sufficient relevant expertise or have access to such expertise6.
The representativeness requirement does not have to be met if an interest group brings a claim with an idealistic purpose and has a very limited financial interest in doing so, or if the nature of the claim brought justifies it7. This exception was applicable in the well-known Urgenda case. The Urgenda Foundation took the State to court and the Court was of the opinion that the State had violated its duty of care. Under Articles 2 and 8 ECHR, the State had a positive obligation to prevent dangerous climate change and had not done enough to catch up8.
The court will assess whether the interest organisation is admissible. To be admissible, the interest group must be non-profit and the legal action brought must have a sufficiently close link to the Dutch legal order9.
Central Register
A WAMCA action must be registered in the Central Register for Collective Actions10. This is necessary to ensure that collective claims that relate to the same event(s) with similar factual and legal issues are brought before the same court as where the first claim was brought. This central register can be found at rechtspraak.nl. This is also where settled claims can be found. See WAMCA-register.
Opt-out Option
After the EB is selected, injured parties can make use of the first opt-out option11. This means that they can indicate that they do not want to be bound by the outcome of the proceedings. The opt-out period is set by the court in an interlocutory ruling and is at least one month. Following the EB’s designation, there is a pause in the proceedings as well so that an attempt can be made to reach a settlement.
If the parties manage to reach a settlement, it has to be submitted to the court in a draft form in which the requirements for a WCAM settlement have to be met12. The judge then determines a collective damage settlement based on the proposals that have or have not been made. In doing so, the judge should determine the damages insofar as possible in categories. The judge must ensure that there is reasonable compensation and that the interests of injured parties who have not made use of the opt-out are adequately safeguarded13.
The court’s ruling binds not only the parties to the proceedings but also the injured parties who have not used the initial opt-out. Unless the ruling concerns the approval of a settlement reached by the parties. In that case, injured parties resident in the Netherlands can make use of the second opt-out. If interested parties do not use either the first or the second opt-out, they are bound by the outcome of the proceedings. Injured parties who at the time of the judgement could not have known about their damages can still decide not to participate at a later stage.
All non-resident injured parties are not automatically bound. They can use their opt-in option. Finally, individual proceedings will be suspended while the collective proceedings are ongoing.
Also read the next part of this article: WAMCA in practice.
1 Stb.2005, 380.
2 Stb. 2019, 447.
3 The Supreme Court of the Netherlands 5 October 1992, ECLI:HR:NL:1992:ZC0706.
4 A.A.L. Oving, ‘De WAMCA onder de loep genomen’, TVP 2020, p. 11-19.
5 Artikel 3:305a lid 2 sub a-e BW; Kamerstukken I 2018/19, 34608, A, p. 2.
6 Kamerstukken II 2016,17, 34608, nr. 3, p. 21 (MvT).
7 Art. 3:305a lid 6 BW; Kamerstukken I 2018/19, 34606, A, p.2-3.
8 Court of Appeal The Hague 9 October 2018 ECLI:NL:GHDHA:2018:2591 (Urgenda/De Staat).
9 Kamerstukken II 2016/17, 34608, nr. 3, p. 24 (MvT).
10 Artikel 3:305a lid 7 BW; Kamerstukken I 2018/19, 34608, A, p.4.
11 A.A.L. Oving, ‘De WAMCA onder de loep genomen’, TVP 2020, p. 11-19.
12 See our prior publication about the WCAM and article 7:907 of the Dutch Civil Code.
13 Artikel 1018i lid 2 Rv; Kamerstukken I 2018/19, 43608, A, p. 9.
