The As-Efficient Competitor Test: A Cornerstone or a Controversy in EU Competition Law?

The As-Efficient Competitor (AEC) test has long been a focal point in EU competition law, serving as a conceptual tool for assessing whether the conduct of a dominant company has exclusionary effects capable of harming competition. Its introduction in the European Commission's 2008 Guidance Paper marked a significant shift toward an effects-based approach, aiming to ensure that competition enforcement focused on conduct that genuinely harms consumers by impairing the competitive process. However, the AEC test has sparked significant debate among scholars, practitioners, and courts, particularly concerning its application and evidentiary role in assessing abuse under Article 102 TFEU. The purpose of this paper is to clarify the meaning and role of the AEC test in EU competition law and to examine why it has generated such significant controversy in its application and interpretation.

This paper focuses on clarifying the AEC test, starting with its theoretical foundation and the general idea of this conceptual framework. It traces the test’s adoption in the European Commission’s 2008 Guidance Paper, explaining how it was conceived as a conceptual principle for assessing anticompetitive foreclosure rather than being limited to a specific empirical procedure, such as a price-cost test. The conflation of the AEC principle with the price-cost test is addressed as a critical misunderstanding, highlighting that the AEC principle serves as a broader standard for evaluating exclusionary conduct. The paper also examines briefly the test’s interpretation and application by the European Courts, revealing its evolution and the recognition that while the AEC principle remains a valid benchmark, the evidentiary tools used to assess it may vary depending on the nature of the conduct. Finally, the paper briefly considers the future of the AEC test in light of the European Commission’s Draft Guidelines on the application of Article 102 TFEU, considering its potential implications for enforcement and competition law.