The Arco case involves nearly 800.000 shareholders of four companies that were established by the most important Belgian union. The problem was that these investment companies highly depended on the Dexia holding which collapsed in 2011. As a result of that, all these people lost their savings. The case is also highly politized and the Belgian Government promised all shareholders in 2011 a state guarantee. However this guarantee was annulled by the European Court of Justice in 2016. SQ was consulted by the Arco Claim Foundation and started litigation on behalf of its members against Belfius Bank and the Belgian State. The Arco case created losses for its shareholders up to 2 billion Euro. Litigation is still going on and Arco shareholders still can join. The foundation is represented by founding SQ partners Geert Lenssens en Niels Van Campenhout.