Terms used in antitrust and competition law to describe actions that are almost always illegal. Typical hard-core violations include cartels and cartel behavior including bid-rigging, price fixing, market and customer allocation (agreeing who gets which customer), output restraints (agreeing to limit output so as to support prices), tying, resale/retail-price-maintenance. Under EU Competition Law, actions that seek to artificially divide the Single Market, i.e., stop goods flowing from one member state to the other can be considered hard-core violations under certain circumstances. In an EU ‘Block Exemption’, the ‘Black List’ of prohibited clauses or provisions usually consists of hard-core items.