Interview with Professor Matthias Weller

July 30, 2026

Interview conducted by Amanda Buonaiuto

Meet Professor Matthias Weller

Professor Matthias Weller is a leading German scholar in the fields of civil law, international civil litigation and arbitration, art and cultural property law. He completed his legal education at the University of Heidelberg (Germany) and St. John’s College at the University of Cambridge (United Kingdom). Prof. Weller continued his academic career at the Harvard Law School, as Joseph Story Fellow for Private International Law, and at the University of Heidelberg, where he completed his doctoral dissertation, supported by the German National Scholarship Foundation, on the public policy control of international choice of forum agreements. Currently, he serves as Director of the Institute for German and International Civil Procedural Law and Chair of the Research Center for Provenance Research, Art and Cultural Property Law at the University of Bonn, Germany.

Through academic work and engagement with governmental institutions, Professor Matthias Weller has become a prominent voice in shaping contemporary approaches to cultural property restitution and alternative dispute resolution methods in Germany.

Receiving funding from the German Government for a five-year research project, the Restatement of Restitution Rules for Nazi-Confiscated Art, which examined restitution practices across jurisdictions and developed guiding principles for resolving claims. Being commissioned by the German Government to lead the International Scientific Study to Strengthen the Advisory Commission, analyzing possible reforms to improve Germany’s restitution process for Nazi-confiscated cultural property.This study led to the establishment of the new Court of Arbitration for Nazi-Looted Cultural Property.

Center for Art Law sincerely appreciates Professor Weller for generously sharing his time and insights in this interview, which was conducted, edited, and supplemented by Amanda Buonaiuto (Lead Researcher of the Nazi-Looted Art Restitution Project for Center for Art Law), who had the privilege of being Professor Weller’s master’s student and academic mentee at the University of Bonn.

Select Publications

Weller, Matthias, The New German “Court of Arbitration for Nazi-Looted Art”, JUSTICE (The Legal Magazine of the International Association of Jewish Lawyers and Jurists) Special Issue „Law and Holocaust“ (2026), https://www.ijl.org/justicem/no77/

Weller, Matthias and Scheller, Tessa. Why a “Restatement of Restitution Rules for Nazi-Confiscated Art”? Observations on the “weighing of interests” in light of the Kohnstamm Report, Network of European Restitution Committees Network-Newsletter (2021), https://lootedart.com/web_images/pdf2022/Network-Newsletter-no.12-December2021.pdf

Weller, Matthias, et al. Restatement of Restitution Rules for Nazi-Confiscated Art, DE Gruyter (2025), https://www.degruyterbrill.com/document/isbn/9783689240134/html

Weller, Matthias. Strengthening the Advisory Commission, commissioned by the Federal Commissioner for Culture and Media (2024), https://kulturstaatsminister.de/fileadmin/user_upload/Downloads/BKM/2024-04-05-bkm-studie-weller.pdf

Weller, Matthias. Guide to the work of the Restitution Committees – Five ways of resolving claims. In search of “just and fair solutions”: Towards the future of the “Washington Principles on Nazi-Confiscated Art”, Commission pour l’indemnisation des victims de spoliations intervenues du fait des législations antisémites en vigueur pendant l’Occupation (CIVS) (2019), https://www.civs.gouv.fr/sites/civs/files/documents/civs-guide-web-dec2019.pdf

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Interview

1) What motivated you to pursue legal studies, and how did you come to enter academia?

I have always been drawn to disciplines of critical thinking. For a while, I considered studying literature or history, but ultimately I chose law. From the very beginning, I found it deeply fascinating, as law engages with every dimension of social life and contributes to the “engineering” of society through the pursuit of justice, however complex and context-dependent that concept may be.

While pursuing my legal education, I had the pleasure to meet (the late) Professor Erik Jayme, who was a leading figure in private international law and one of the pioneers of art law in Germany. He later became my academic mentor and PhD supervisor, playing a pivotal role in shaping my professional path. His vision of academic life greatly inspired me and ultimately convinced me to pursue an academic career, where I have remained ever since, despite occasional “field trips” into legal practice, including working at large international law firms, as expert witness as well as arbitrator.

2) What first drew you to the field of looted art restitution, and how did it become a central part of your professional work?

In 1998, I had the privilege to be one of the Fellows of the Joseph Story Research Program^[1] at Harvard Law School. At the time, the recently-adopted Washington Principles were the subject of intense discussion on campus, generating many panel debates, and introducing me to numerous scholars and practitioners working on looted art restitution. Coming from Germany, a country that bears a historical responsibility for the Holocaust, these encounters were especially meaningful.

During my time in the United States, my perspective on the Holocaust changed profoundly, evolving from a theoretical and abstract understanding into a personal connection with history, which reinforced my conviction that issues of restitution and historical justice are of great importance.

I vividly remember visiting the United States Holocaust Memorial Museum in Washington DC. At the end of the exhibition, visitors could listen to recorded testimonies from Holocaust survivors, and I remember spending hours there. Although I had previously visited concentration camps in Germany, including Dachau and Buchenwald, this experience affected me more deeply than anything else. It was certainly one of the driving forces behind my decision to engage with looted art restitution as a scholar.

For many years, however, restitution remained just one component of my broader research agenda. I first had to build my career within more traditional legal disciplines, particularly private international law and international commercial dispute resolution. A significant turning point came in 2018, when the University of Bonn established Germany’s first professorship in Art and Cultural Property Protection Law and I was appointed to the Alfried Krupp von Bohlen und Halbach Foundation chair, and the position of Director of the Institute for German and International Civil Procedural Law. This institutional foundation enabled me to engage much more deeply with art law and, in particular, with restitution, allowing it to become a central focus of my academic work.

3) What motivated the development of the Restatement of Restitution Rules for Nazi-Confiscated Art? And what role does it have in restitution discussions today?

Since 1998, I have closely observed the development of restitution approaches related to Nazi-confiscated objects. Over the years, I was often concerned by contradictory assumptions, and practice inconsistencies related to those pieces, to a degree I had never encountered in any other law field. This ultimately led me to the plan of creating a resource extremely useful in navigating such a complex field and providing a solid basis for evaluating the arguments, decisions, and policies surrounding restitution: Restatement of Restitution Rules for Nazi-Confiscated Art.

The idea was first presented in 2012, during a conference which reunited the five European restitution Committees. The audience reacted kindly, albeit somewhat indulgently, to what may have seemed an ambitious proposal from a younger colleague. At the time, few people believed the project would be feasible, including myself. Seven years later, the project finally came to life after securing funding from the German Federal Government.

Together with a team of ten PhD researchers from the University of Bonn, approximately 1,300 restitution cases from the principal European jurisdictions (Germany, Austria, the Netherlands, France, the United Kingdom, and Switzerland) were collected and analyzed. Recurring principles, normative structures, and patterns of legal reasoning were researched. Based on these findings, we developed a set of black-letter rules accompanied by detailed commentaries and reports, inspired by the methodology and style of the north-american Law Restatements.

The Restatement is intended to become an increasingly important point of reference in restitution matters. Whether in evaluating individual claims, developing legal frameworks, or assessing the reasoning behind restitution decisions. One of the most fundamental expectations is that decisions and rules should be supported by clear and transparent reasoning, and the Restatement seeks to contribute to that objective by identifying and explaining the principles that have shaped restitution practice across jurisdictions.

4) Could you briefly explain the key differences between the Limbach Commission and the new German Court of Arbitration for Nazi-Looted Cultural Property?

The former Limbach Commission functioned as a mediation and advisory body that could only become active once both parties agreed to submit their dispute to the Committee. Its decisions took the form of non-binding recommendations, and it operated under a principle of subsidiarity: parties were expected to first attempt to reach a bilateral settlement based on a “just and fair solution” before submitting the case to Commission.

As a result, the Commission issued only around 25 recommendations over the course of more than twenty years, despite the fact that tens of thousands of restitutions took place in Germany during the same period. The Committee did not attempt to deliver general principles or rules, rather, it considered each case as a singularity. While this approach was understandable in light of the individual histories and experiences of the victims, restitution cases also raise recurring legal questions. The same issues arise repeatedly, and it becomes problematic when such questions are addressed inconsistently or without clear reasoning. The composition of the Limbach Commission also drew attention, as Jewish representation remained limited, with only two Jewish members serving on a ten-member institution.

The new German Court of Arbitration for Nazi-Looted Cultural Property operates under a detailed set of procedural rules specifically designed to guarantee due process, with those guarantees being legally enforceable. The uniqueness of this arbitration framework lies in the fact that public institutions have committed themselves to issuing standing offers to arbitrate claims concerning all cultural objects in their collections. Once such a standing offer has been made, a claimant need only accept it for a binding arbitration agreement to come into existence. Although the process of issuing standing offers is still ongoing, many public institutions have already done so, and these commitments are publicly available.

This structure avoided the complexities of the German legislation, which would have required coordination across Germany’s federal, state, and municipal levels. More importantly, it created, for the first time, a system capable of producing legally binding decisions based on the Washington Principles through a specialized set of rules known as the Assessment Framework. Another important aspect from it, is that the entire mechanism was developed in consultation with representatives of the Jewish community, and the list of accredited arbitrators was established jointly. Each party selects two arbitrators, and those four arbitrators must then agree on a presiding arbitrator. The costs of the arbitral tribunal are paid by the German government^[2].

5) What, in your view, were the key factors that led Germany to move from the Commission model to the new Arbitration Tribunal?

There was the clear sense that something differently must be done, given a larger number of deficiencies. What remained less clear, however, was which changes would be helpful for the restitution field. Many professionals advocated for parliamentary legislation, but it was equally evident that such an undertaking would be highly complex and would offer no guarantee of success. Against this background, the idea of establishing an arbitral framework emerged as an innovative alternative. This approach offered several advantages, and most importantly, an arbitration framework can be specifically tailored to the unique needs of restitution proceedings. For this reason, we proposed this model, and it is ultimately the approach that governments across all levels of the Federal Republic of Germany decided to adopt.

It is important to note that the introduction of the arbitral framework does not block future legislative efforts. On the contrary, the new system may facilitate such efforts. With the introduction of the Assessment Framework for the arbitral tribunals, there is now a concrete model that legislators can draw upon. It provides not only substantive guidelines for resolving restitution claims, but also practical ideas regarding procedure, judicial balance, and representation within the decision-making body.

6) Do you think this new approach could shape future restitution mechanisms, particularly in countries that already have committee-based systems?

In my view, several committee-based restitution systems in Europe function effectively, and I do not see any immediate need for reform in those jurisdictions. However, the situation is different in countries that do not offer a dedicated alternative dispute resolution mechanism for restitution claims.

The United States is a particularly interesting example. Despite having played a leading role in the development of both the Washington Principles and the subsequent Best Practices, it does not have a national restitution commission or a comparable mechanism for alternative dispute resolution. This stands in contrast to Article 11 of the Washington Principles^[3], which encourages nations to develop national processes for implementing the Principles, particularly through alternative dispute resolution mechanisms for ownership disputes. It also contrasts with Principle I of the Best Practices^[4], which expressly encourages the use of alternative dispute resolution to avoid litigation.

Of course, there is now the new HEAR Act, which removes certain legal obstacles. Nevertheless, litigation remains the only option available to claimants seeking restitution in the United States. Over the years, when discussing this with North-American colleagues, I have often heard that the federal structure of the country presents challenges to the creation of a national restitution mechanism. Yet Germany is also a federal state. The development of the new arbitration framework demonstrates that federalism need not be an obstacle to creating an effective and coordinated restitution process. For that reason, I believe the German model may offer useful inspiration.

7) Could you provide comments on the eligibility of claimants and the standing offer system from the new Court, explaining the details of each?

In principle, any claimant is eligible if the loss of the cultural object happened as a result of Nazi persecution in Germany between 30 January 1933 and 8 May 1945. If a claimant wishes to initiate arbitration, the process is relatively straightforward. The claimant simply needs to sign the arbitration agreement and submit it to the Office of the Court. A template agreement is available on the Court’s website to facilitate this process. In addition, where claims involve a community of heirs, all heirs must be appropriately represented within the proceedings.

Regarding the standing offer system, there are two options: if the public institution has already issued a standing offer to arbitrate, a claimant need only accept that offer for the arbitration agreement to come into existence. If the relevant public holder has not yet issued a standing offer, the Office of the Court will invite it to do so, and it is generally expected that the institution will comply. It is important to note that standing offers do not extend to objects for which a just and fair solution has already been reached.

8) In the event held on 28 January 2026 “The new German “Court of Arbitration for Nazi-looted Cultural Property” you mentioned that the Court will have reduced standards of proof (e.g. for ownership), including a new presumption of ownership based on actual or former possession of the object. Could you comment briefly about this matter?

At the beginning of the reform process, we received some complaints against the new Court, claiming that it would apply the high standards of proof typically required in regular civil proceedings. However, this is not reflected in the rules of the arbitration tribunal. Instead, the new system introduces several mechanisms that lower the required level of certainty and establish presumptions, including the presumption of former ownership based on former possession of the object. This element is clearly favorable to claimants, as it helps address gaps in provenance research and facilitates the assessment of claims where complete ownership records no longer exist.

10) In the same event, while discussing the assessment framework of the new Court, you noted that restitution will be the primary remedy, while direct monetary compensation will not be available. Could you explain the reasoning behind this approach? In particular, why are other “fair and just solutions” reinforced by the Best Practices for the Washington Conference Principles on Nazi-Confiscated Art not being encouraged?

This is a political decision. In the International Scientific Study “Strengthening the Advisory Commission”, we argued in favour of financial compensation as an option in order to create nuanced solutions, where necessary. However, implementing such an approach would require a dedicated budget. I assume that this consideration was one of the main reasons why monetary compensation was ultimately excluded.

Germany is not alone in adopting this approach. Austria, for example, also limits the available outcomes to either restitution or rejection of the claim. In my view, this is not necessarily the optimal solution. On the other hand, the Austrian regime has resulted in a restitution rate of more than 80 percent, which is certainly a meaningful accomplishment.

Nevertheless, other jurisdictions have taken a different path. France and Switzerland make use of proportional compensation arrangements as part of their restitution practice. In my opinion, this offers greater flexibility and allows decision-makers to tailor outcomes more closely to the specific circumstances of individual cases.

11) Are you also participating in the drafting of the new restitution legislation in Germany? What changes can we possibly expect when this law comes into force?

The current German Government has once again reaffirmed^[5] its intention to enact a new restitution legislation. I understand this announcement as primarily addressing the issue of cultural objects held in private hands, as opposed to objects held by public institutions, but we will have to wait and see how the legislation develops.

From an academic perspective, we are closely following these developments. For example, I am currently supervising a very comprehensive PhD thesis on this topic, which will be published soon.

This future legislation will have to address several important questions, including the establishment of an appropriate assessment framework for cases involving private ownership. It will also need to include a compensation mechanism for private owners who lose their property as a result of restitution to former owners. This is required in light of constitutional protections for private ownership.

12) Could you comment on the relationship between this future restitution law and the new Arbitration Tribunal?

From my perspective, while the Court of Arbitration will continue to handle claims involving public owners, the future legislation could potentially address litigation proceedings against private owners.

About the Author

Amanda Buonaiuto is a Brazilian lawyer with a specialization in Nazi-looted art restitution, earned through her LL.M. at the University of Bonn, Germany. With additional expertise in provenance research, she currently leads the research of the Nazi-Era Looted Art Restitution Project at the Center for Art Law.

Additional resources

Bundesministerium der Justiz und für Verbraucherschutz, Law on Facilitating the Enforcement of the Return of Cultural Property Seized as a Result of Nazi Persecution (2024), https://www.bmjv.de/SharedDocs/Gesetzgebungsarchiv/2024_NS-Raubkunst.html?nn=262054

Der Beauftrage der Bundesregierung für Kultur und Medien, Nazi-looted art: Processing and restitution. Arbitration of Nazi-Looted Art (2025), https://kulturstaatsminister.de/aufarbeiten-und-erinnern/aufarbeitung-der-ns-gewaltherrschaft/ns-raubgut/schiedsgerichtsbarkeit-ns-raubgut

Mawick, Zacharias. Recent Developments in German Restitution Policy, The Institute of Art & Law (2026), https://ial.uk.com/german-restitution-policy/

University of Bonn, Prof. Dr. Matthias Weller, Mag. rer. publ. MAE Wissenschaftliches Profil, (2026), https://www.jura.uni-bonn.de/de/forschung-und-lehre/lehrende/lehrstuhl-prof-dr-weller/mitarbeitende-am-lehrstuhl/prof-weller

Weller, Matthias. Wie Deut­sch­lands neues Schieds­ge­richt funk­tio­niert, Legal Tribune Online (2025), https://www.lto.de/recht/hintergruende/h/restitution-ns-raubkunst-neues-schiedsgericht-deutschland-wie-es-arbeitet

Select References

1. Murray, Peter. Conflict of Laws in a Globalized World: 2 – Arthur Taylor von Mehren and the Joseph Story Research Fellowship, Cambridge University Press (2007), https://www.cambridge.org/core/books/abs/conflict-of-laws-in-a-globalized-world/arthur-taylor-von-mehren-and-the-joseph-story-research-fellowship/368AA21D8F30F7706DA5C08E5860251A ↑
2. Section 31 – Costs from the Court of Arbitration for Nazi-looted Cultural Property Rules of Arbitration: “The parties do not incur any costs by referring a case to the arbitration panel. The costs of the arbitration panel are not charged to the parties. The parties must bear any costs they themselves incur. This applies for example to the costs of legal counsel and representation.”. See https://kulturstaatsminister.de/fileadmin/user_upload/Downloads/Aufarbeiten/Verwaltungsabkommen_Schiedsgerichtbarkeit/Verwaltungsabkommen_Schiedsgerichtbarkeit_barrierefrei/Rules_of_Arbitration_ENG_bf.pdf ↑
3. Article 11 of Washington Principles: “The Nations are encouraged to develop national processes to implement these principles, particularly as they relate to alternative dispute resolution mechanisms for resolving ownership issues.”. ↑
4. Principle I of the Best Practices for the Washington Conference Principles on Nazi-Confiscated Art: “I. Countries are encouraged to create an independent expert body whose composition may be the states’ responsibility, to which unilateral access is available that can adjudicate cases of art and cultural property and arrive at or recommend a binding or non-binding decision (for example, the use of commissions in Austria, France, Germany, Netherlands, and the United Kingdom). Such bodies should have balanced, expert, and representative membership. Use of alternative resolution mechanisms is encouraged to avoid litigation.“. ↑
5. Deutschlandfunk, Interview der Wohe: Kulturstaatsminister Weimer spricht sich für Restitutionsgesetz aus – Rückgabe von Raubgut “Frage der Moral” (2026), https://www.deutschlandfunk.de/kulturstaatsminister-weimer-spricht-sich-fuer-restitutionsgesetz-aus-rueckgabe-von-raubgut-frage-der-114.html ↑