The European harmonization efforts produced under the European Commission's Financial Services Action Plan in the field of capital market regulation have created an impressive body of investor protection oriented rules. Strikingly, the harmonization directives remain largely silent on the penetration of these investor protection rules into the private law sphere of the relation between financial services suppliers and investors. Taking the Markets in Financial Instruments Directive 2004/39/EC as an illustration, we analyse in this paper to what extent the investor protection rules devised at EU level are devised to produce effects in private law relations, and how this is reflected in the laws of selected national jurisdictions. We focus in this regard at on the civil law effects of the MiFID provisions regarding (i) authorization and prudential requirements for regulated firms and (ii) conduct of business rules to be observed by the suppliers of investment services. We observe quite some "blind spots" in MiFID regarding important aspects of the private law relationship. More generally, MiFID is illustrative of the "regulatory atrophy" with regard to opportunities for private enforcement of the investor protection rules. We submit that the legal uncertainty induced by the disparities in national liability regimes may create disincentives for suppliers of investment services to effectively take advantage of the European passport regime.