EU Regulation 2271/1996 (known as the Blocking Regulation) counteracts the extraterritorial effect of the US Iran Sanctions Act of 1996 (ISA). The Blocking Regulation will arguably also apply to CISADA since this is an amendment to ISA. The effect is to prohibit EU companies and nationals from complying with CISADA where to do so would adversely affect the economic interests of that company or national. As a practical matter, given the broad political alignment between the EU and the US towards Iran, the extent to which the Regulation will be invoked is not known. There are procedures set out in both EU and US law to seek derogations and/or clarification.