Few stakeholders are aware of cases where the conditions of execution - including the clauses on adjustments over time - have had a discriminatory effect or represented an unjustified barrier to the freedom to provide services or freedom of establishment. Those contributors who perceive discriminatory effects complain in particular about the different treatment of public and private companies (preferential tax treatment and the lack of insolvency risk of public undertakings). One stakeholder cites "evergreen" clauses (i.e. requiring the private contractor to keep the technical standard of a project at the state of the art) and automatic renewal clauses as problematic.