1.   Horizon 2020 shall contribute to the strengthening of public-public partnerships, as and when appropriate, where actions at regional, national or international level are jointly implemented within the Union.

Particular attention shall be paid to Joint Programming Initiatives between Member States. Joint Programming Initiatives receiving support from Horizon 2020 shall remain open to the participation of any Member State or associated country.

2.   Public-public partnerships may be supported either within, or across, the priorities set out in Article 5(2), in particular through:

     (a) an ERA-NET instrument using grants to support public-public partnerships in their preparation, establishment of networking structures, design, implementation and coordination of joint activities, as well as Union topping-up of no more than one joint call a year, and of actions of a transnational nature;

     (b) Union participation in programmes undertaken by several Member States in accordance with Article 185 TFEU where the participation is justified by the scope of the objectives pursued and the scale of the resources required.

For the purposes of point (a) of the first subparagraph, top-up funding shall be conditional on the demonstration of the added value of the action at Union level and on prior indicative financial commitments in cash or in kind of the participating entities to the joint calls and actions. One of the objectives of the ERA-NET instrument may, where possible, be to harmonise rules and implementation modalities of the joint calls and actions. It may also be used in order to prepare for an initiative pursuant to Article 185 TFEU.

For the purposes of point (b) of the first subparagraph, such initiatives shall only be proposed in cases where there is a need for a dedicated implementation structure and where there is a high level of commitment of the participating countries to integration at scientific, management and financial levels. In addition, proposals for such initiatives shall be identified on the basis of all of the following criteria:

     (a) a clear definition of the objective to be pursued and its relevance to the objectives of Horizon 2020 and broader Union policy objectives;

     (b) indicative financial commitments of the participating countries, in cash or in kind, including prior commitments to align national and/or regional investments for transnational research and innovation and, where appropriate, to pool resources;

     (c) the added value of the action at Union level;

     (d) the critical mass, with regard to the size and the number of programmes involved, the similarity or complementarity of activities and the share of relevant research they cover;

     (e) the appropriateness of Article 185 TFEU for achieving the objectives.