If you are in doubt about whether the sanction rules bar you from doing business with a particular party, it is unwise to rely solely on the sanctions lists based on the relevant EU regulations.
It is worth the effort to carefully check whether the parties listed are all in fact sanctioned (or still sanctioned).
In January of this year, the Dutch Ministry of Foreign Affairs issued an updated version of the Iran Handbook (in Dutch). The handbook explains the sanctions against Iran and their relaxation last year. The handbook also contains a warning that certain parties are still on the sanctions list even though they are no longer sanctioned. The European Court of Justice annulled the decision underlying the sanctioning of these parties but such changes have not been incorporated in the consolidated versions (updates) of the relevant EU regulations.
Last year we discovered first-hand the uncertainty to which this can give rise. We were asked by a client to perform a sanctions check on a particular party. According to the database we use for background/know your customer checks, the party in question should have been free of sanctions as from a specific date. However, the text of the relevant EU sanctions regulation, which is binding, still indicated that he was a sanctioned party. We learned from further investigation that the decision underlying the sanctioning of this party had been annulled by the European Court of Justice. Our inquiries with the Ministry of Foreign Affairs as to whether the EU had forgotten to amend the regulation accordingly and whether this party was or was not sanctioned were inconclusive. Ultimately the European Commission confirmed, at our request, that the party in question was indeed no longer sanctioned.