Contract number: [ complete ]   2019  ‘Supplier portal’ : the  e-PRIOR portal, which allows the contractor to exchange electronic  business documents, such as invoices, through a graphical user interface; its main features can  be found in the supplier portal overview document  available on: http://ec.europa.eu/dgs/informatics/supplier_portal/doc/um_supplier_portal_overview.pdf In the event of a joint tender submitted by a group of economic operators and where the group  does not have legal personality or legal capacity, one member of the group is appointed as  leader of the group. Each provision of this FWC is severable and distinct from the others. If a provision is or  becomes illegal, invalid or unenforceable to any extent, it must be severed from the remainder  of the FWC. This does not affect the legality, validity or enforceability of any other provisions  of the FWC, which continue in full force and effect. The illegal, invalid or unenforceable  provision must be replaced by a legal, valid and enforceable substitute provision which  corresponds as closely as possible with the actual intent of the parties under the illegal, invalid  or unenforceable provision. The replacement of such a provision must be made in accordance  with Article II.11. The FWC must be interpreted as if it had contained the substitute provision  as from its entry into force.  II.4. PROVISION OF SERVICES  8 OJ L 94 of 28.03.2014, p. 65  18  II.4.6  The contractor must not present itself as a representative of the contracting authority  and must inform third parties that it is not part of the European public service.  II.4.5 All periods specified in the FWC are calculated in calendar days, unless otherwise  specified. II.4.4  The contractor must obtain any permit or licence required in the State where the services  are to be provided.  II.4.3  The contractor must comply with the minimum requirements provided for in the tender  specifications. This includes compliance with applicable obligations under  environmental, social and labour law established by Union law, national law and  collective agreements or by the international environmental, social and labour law  provisions listed in Annex X to Directive 2014/24/EU $^{8}$.  II.4.2  The contractor must provide services of high quality standards, in accordance with the  state of the art in the industry and the provisions of this FWC, in particular the tender  specifications and the terms of its tender. II.4.1   Signature of the FWC does not guarantee any actual purchase. The contracting authority  is bound only by specific contracts implementing the FWC.  II.2. ROLES AND RESPONSIBILITIES IN THE EVENT OF A JOINT TENDER  II.3. SEVERABILITY 