We examine the familiarity hypothesis of home bias by studying how foreign ownership of Swedish firms is affected by the mandatory adoption of IFRS. We decompose foreign investors into institutional and non-institutional investors. Foreign investors are further decomposed into EU (IFRS adopting countries) and non-EU residents (non-IFRS adopting countries). We analyse the equity investments of these foreign investor groups in Sweden during the period of 2001-2007. We find that after the mandatory adoption of IFRS, foreign ownership/owners from countries that adopted IFRS and particularly those from the EU increased. These effects are particularly strong in small firms. Foreign institutional investors increased their ownership stake after the mandatory IFRS adoption, whereas foreign non-institutional investments were not affected significantly by the IFRS adoption. In contrast to ownership from non-adopting countries, ownership from the EU increased in firms with both more and less tangible assets. Similarly, foreign ownership from the EU increased in firms with both concentrated ownership and dispersed ownership after the adoption. Because Sweden has already had strict legal enforcement and a low level of earnings management prior to the adoption, our results suggest that increased foreign ownership is due to better abilities to compare firms rather than an improved quality.