The OCTs have been explicitly invited by the EU treaty to join the EU-OCT Association (OCTA). They were listed in the Article 198 of the Treaty on the Functioning of the European Union, which aside from inviting them to join OCTA, also provided them the opportunity to opt into EU provisions on the freedom of movement for workers and freedom of establishment. Yet, the freedom of establishment is limited by Article 203 TFEU and the respective Council Decision on OCTs. Its Article 51(1)(a) prescribes only that "the Union shall accord to natural and legal persons of the OCTs a treatment no less favourable than the most favourable treatment applicable to like natural and legal persons of any third country with whom the Union concludes or has concluded an economic integration agreement." Again this can be, according to Article 51(2)(b) limited. The obligations provided for in paragraph 1 of this Article shall not apply to treatment granted under measures providing for recognition of qualifications, licences or prudential measures in accordance with Article VII of the General Agreement on Trade in Services (GATS) or the GATS Annex on Financial Services.