Parties défenderesses: Parlement européen (représentants: L. Visaggio et P. Schonard, agents); Conseil de l’Union européenne (représentants: M. Simm et J. Herrmann, agents); et Commission européenne (représentants: initialement C. Cattabriga et F. Schatz, puis C. Cattabriga et S. Grünheid, agents)
Defendants: European Parliament (represented by: L. Visaggio and P. Schonard, acting as Agents), Council of the European Union (represented by: M. Simm and J. Herrmann, acting as Agents), and European Commission (represented initially by C. Cattabriga and F. Schatz, and subsequently by C. Cattabriga and S. Grünheid, acting as Agents)