The Agreement establishing the EMBC states in Article II.3:
Projects studied by the Conference which only some Members are disposed to execute shall be termed Special Projects. Any Special Project shall be approved by the Conference by a two-thirds majority of the Members present and voting. The execution of a Special Project shall be the subject of a special agreement between the States participating in it. Any Member is entitled to participate at any later time in a Special Project which has already been approved.
This article allows a subset of member states to work together within the framework of the EMBC on joint activities furthering co-operation in molecular biology.
The article was initially drafted with a view to working towards the establishment of a European Laboratory for Molecular Biology, which was one of the goals of the founding members of EMBO.