Ex-post Analysis of the TeliaSonera-Chess 2005 Merger

The European mobile telecom market has experienced a large wave of mergers over the past two decades. Many of these mergers were cleared unconditionally by the competition authorities in charge, some of them were cleared with commitments by the merging parties and a few were blocked or withdrawn before a likely prohibition decision.

These merger decisions were based on an ex-ante analysis of the possible future impact of the proposed transaction on the market. Ex-post analyses can complement such ex-ante analyses by identifying the actual impact of merger transactions. While ex-post analyses cannot be used to change the decision of competition authorities, such analyses of merger decisions have the potential to single out competition authority decisions that turned out to be incorrect ex-post and identify market conditions that lead to such ex-post incorrect decisions.

In our paper, we provide an ex-post analysis of the 2005 TeliaSonera-Chess merger in the Norwegian mobile telecommunication market.

Applying a difference-in-difference approach and a synthetic control group method we find no evidence of the merger increasing prices. Possible explanations for these findings include:

The paper has been published in De Economist and stems from a research project we did for the Norwegian Competition Authority in 2018-2019.