On 17 October 2016 the European Commission and the US Government signed an agreement which facilitates cooperation between US organisations and Horizon 2020 participants. The aim of the agreement is to enable US researchers to cooperate with Horizon 2020 projects outside the framework of the grant agreement, and to increase cooperation in research projects.
The agreement (called Implementing Arrangement) has been set up for those cases where the US organisations are funded by the US and do not receive any funding from the Horizon 2020 programme. It simplifies cooperation between a selected Horizon 2020 project and a US entity by enabling researchers to organise their cooperation outside the formal Horizon 2020 Grant Agreement signed for each project, in accordance with applicable laws, rules, policies, and regulations of their respective funding programmes.
An FAQ on this EU-US Implementing Arrangement has now been prepared by the EC services, in cooperation with their US counterparts, and can be found here: http://ec.europa.eu/research/iscp/pdf/eu-us_coop_faq.pdf