Miralles-Marcelo, José LuísMiralles-Quirós, Maria del MarLisboa, Inês2018-04-272018-04-2720120210-2412http://hdl.handle.net/10400.8/3224The objective of this study is to analyze return differences between family and non-family firms quoted on the Spanish stock market over the 1999-2008 period. Furthermore, we compare risk exposure for these kinds of firms; the abnormal profits that may be obtained with a zero cost trading strategy based on being long in family firms and short in non-family firms; and the founder and size effects on performance. Our main results indicate the possibility of gaining abnormal profits trading on small family firms and selling non-family firms. We also observe a significant higher beta risk for family businesses directly managed by their founders. These results are especially relevant for institutional and individual investors, for academics, and the professional managers of these companies.spaFamily firmsReturnSizeLiquidityDebtjournal article