Anti-competitive effects of partial cross-ownership: Experimental evidence

In theory, partial cross-ownership affects product prices and consumer welfare negatively, but empirical evidence is highly controversial. For competition policy it is important whether such effects are substantial enough to cause action. We report a lab experiment on a Cournot duopoly with symmetric passive cross-ownership in which we increase the degree of cross-ownership from 10% (treatment LOW) to 40% (treatment HIGH). We find an increase in price that is substantial enough to be considered problematic from an anti-trust perspective. In addition we show that part of the price increase is caused by increasing collusion.