The European Commission (EC) says it is referring Spain, Poland and the Czech Republic to the European Court of Justice for failing to transpose the Markets in Financial Instruments Directive (MiFID) in national law.
The directive came into force on 1 November 2007 but EU member states were required to implement the rules into domestic law by 31 January 2008.
In April last year EU internal market commissioner Charlie McCreevy threatened infringement proceedings against member states that failed to implement MiFID regulations into domestic law. By July just eight of the 27 EU member states had transposed the directive into national law, but most countries managed to comply in time.
The EC says it is now referring those that haven't - Spain, Poland and the Czech Republic - to the European Court of Justice over non-implementation of MiFID.
A key feature of MiFID is the ability for investment firms to use the authorisation obtained in one member state to provide services in another.
"The benefits of this regime cannot be fully realised by firms from member states that have not transposed the directives, and also by firms from other member states wishing to operate on the territory of member states that are late in transposing," argues the EC.