This thesis investigates the limitations that the proportionality test imposes on a patentee's entitlement to injunctive relief under European Union (EU) law. It has long been established orthodoxy that a patentee whose valid patent is infringed is entitled to injunctive relief requiring immediate termination of the infringement. In recent years, however, that orthodoxy has come under fire. Industry stakeholders and legal scholars worry that in some circumstances such injunctions can have disproportionate effects. Courts seem receptive to these concerns. The European Court of Justice (ECJ) has emphasised that courts must make case-by-case assessments when issuing remedies for intellectual property (IP) infringements. National courts have followed suit and acknowledged that exceptions exist to the patentee's entitlement to injunctive relief.
The tide is therefore clearly turning, but little is known about this proportionality test's substance. This thesis makes the case for a European proportionality framework with three dimensions: overreach, abuse, and conflicts with rights of third parties. Underlying each element of the framework is the principle that a patentee's effective sphere of exclusivity should be commensurate with their inventive contribution. The framework's scope is circumscribed not only by this principle but also by the problems with contemporary patent law that proportionality can legitimately be called upon to resolve. It derives from EU law and its principal legal basis is Directive 2004/48/EC (the Enforcement Directive).
The ambition of this thesis is to offer a proportionality framework that is workable for patent courts, predictable for litigants, effective in practice, and in conformity with EU law. It hopes to be a source of inspiration in years to come for courts and scholars as they grapple with the limits that proportionality must set on patent enforcement.