Bos, IwanHarrington, Joseph E2023-05-222017-01-232015-02-012017-09-12https://repository.upenn.edu/handle/20.500.14332/5229This article examines endogenous cartel formation in the presence of a competition authority. Competition policy is shown to make the most inclusive stable cartels less inclusive. In particular, small firms that might have been cartel members in the absence of a competition authority are no longer members. Regarding the least inclusive stable cartels, competition policy can either decrease or increase their size and, in the latter case, the collusive price can rise.This is the peer reviewed version of the following article: Bos, I. and Harrington, J. E. (2015), COMPETITION POLICY AND CARTEL SIZE. International Economic Review, 56: 133–153. doi:10.1111/iere.12097, which has been published in final form at http://dx.doi.org/10.1111/iere.12097. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving: http://olabout.wiley.com/WileyCDA/Section/id-820227.html#termsBusinessEconomicsPublic Affairs, Public Policy and Public AdministrationArticle