The joint tender must clearly indicate the role and tasks of each member and of the  Group leader  who will act as the  Contracting authority 's contact point for the contract's administrative or  financial aspects and operational management. The  Group leader  will have full authority to bind  the group and each of its members during contract execution. If the joint tender is successful, the  Contracting authority shall sign the contract with the Group leader, authorised by the other  members to sign the contract on their behalf via power of attorney drawn up in the model  attached in  Annex 4 .  Changes in the composition of the group during the procurement procedure (after the deadline  for submission of requests to participate and before contract signature) shall lead to rejection of  the request to participate/tender except in case of a merger or takeover of a member of the group  (universal succession), provided that the new entity has access to procurement (see  Section 2.2 )  and is not in an exclusion situation, (see  Section 3.1 ).  In any case the selection criteria must be still fulfilled by the group and the terms of the  originally submitted request to participate/tender may not be altered substantially, i.e. all the  tasks assigned to the former entity must be taken over by the new entity member of the group,  the change must not make the subsequent tender non-compliant with the tender specifications,  and the evaluation of award criteria of the originally submitted tender may not be modified.  Subcontracting is the situation where the contractor enters into legal commitments with other  economic operators which will perform part of the contract on its behalf. The contractor  retains full liability towards the  Contracting authority for performance of the contract as a  whole. The following shall not be considered subcontracting: a) Use of workers posted to the contractor by another company owned by the same group  and established in a Member State (“intra-group posting” as defined by Article 1, 3,  (b) of Directive 96/71/EC concerning the posting of workers in the framework of the  provision of services).  b) Use of workers hired out to the contractor by a temporary employment undertaking or  placement agency established in a Member State (“hiring out of workers” as defined  by Article 1, 3, (c) of Directive 96/71/EC concerning the posting of workers in the  framework of the provision of services).  c) Use of workers temporarily transferred to the contractor from an undertaking  established outside the territory of a Member State and that belongs to the same group  (“intra-corporate transfer” as defined by Article 3, (b) of Directive 2014/66/EU on the  conditions of entry and residence of third-country nationals in the framework of an  intra-corporate transfer) .  d) Use of staff without employment contract (“self-employed persons working for the  contractor”), without the tasks of the self-employed persons being particular well- defined parts of the contract.  e) Use of suppliers and/or transporters by the contractor, in order to perform the contract  at the place of performance, unless the economic activities of the suppliers and/or the  transporting services are within the subject of this call for tenders (see  Section 1.4 ). 2.3.2. Subcontracting  TEMPLATE: Restricted procedure - Tender specifications Part 1 Administrative Specifications  JRC R.9 - IMS-JRC-S3.1-TMP-0048 - v.1.0 17/02/2020 M(EN)  Page 8 of 32 