Immaterialgüter- und Wettbewerbsrecht

Unjustified Threats of Patent Infringement -Intellectual Property Approach or Unfair Competition Approach?

Unjustified threats of patent infringement can be harmful to businesses and individuals’ legitimate interests, and act as a restriction on the free trade. The project is to pursue an optimal approach tackling cases of unjustified threats cases of patent infringement, and this general conclusion will also be proposed especially for the EU law system.

Last Update: 12.01.21

A patentees’ cease and desist letter can be a lawful enforcement of their exclusive rights, however, it can become unlawful if it is communicated inappropriately. This doctorate project focuses on the concrete criteria for the assessment of unjustified threats of patent infringement in the UK, the US, Germany and China. Based upon the country reports, a comparative analysis that combines the intellectual property law approach and the unfair competition law approach will be conducted; the questions of which approach and which standard of liability that can be applied globally and feasibly will be addressed; this will serve as an advised model for the EU level.The dissertation adopts two methodologies, functional comparative law and systematisation.

Functionalism compares divergent legal solutions to common real-life problems as well as ways of solving conflicts of interest at the micro-level. This methodology will be examined in Chapters 2 to 5. Chapter 2 will primarily deal with a common and concrete legal problem, namely, the general issues of threats of patent infringement. After this, Chapter 3 tries to offer a clear picture of how different legal systems resolve this common problem, including from the perspectives of statutes and judicial practices.

The UK unjustified threats regime has kept holding the emphasis on the types of warning letters since its introduction in 1883, which embodies the unfair competition approach. The illegality can be ruled out when threats are addressed at primary actors, in respect of either a primary or a secondary infringement. Seeing that recipients of threats are the bottom line, the criterion assessment of unjustified nature deployed in the UK legal systems exemplifies the ex ante analysis. The pictures in the other three legal systems are more involved. The current German and Chinese judges have undergone a change in attitude towards the principle of liability, and turn to consider all circumstances in each individual case. This includes the examination of the ways to issue warning letters, and the problem of whether the prudential obligations have been complied with. Among the American judges, the benchmark for deciding cases of justified warning letters has shifted from the old bad faith standard to the so-called double bad faith criteria. The new yardstick sets the objective baselessness as the primary requirement, followed by the subjective intent condition. If a warning letter is objectively accurate, the patentee’s bad faith would not be examined. Hence, considering the objective element needs to be prioritised before reaching the question of the patentee’s intent. In this context, the current US legal system tends to embody the rule of intellectual property in the accurateness requirement and the rule of unfair competition in the subjective bad faith prerequisite.Based on the country reports, a comparison of the four jurisdictions’ similarities and differences will be carried out in Chapter 4. Chapter 5 examines proportionality test that will assist in a critical evaluation of the examined legal solutions.

The task of systematisation is to seek general rules and then form these principles into an organised and rational system. Chapter 6 will adopt the methodology of systematisation, and pursue an optimal approach tackling cases of unjustified threats cases of patent infringement which is grounded in the conducted comparative analysis.


Doctoral Student

Minyu Zheng

Doctoral Supervisor

Prof. Dr. Ansgar Ohly (LL.M)

Main Areas of Research

II.5 Rechtsdurchsetzung und Streitbeilegung