On 22 June during the EU summit in Brussels the leaders of the EU 27 have agreed on the process to be followed for relocating the European Medicines Agency and the European Banking Authority. Both EU agencies are based in London and will need to leave the UK capital following the triggering of article 50.
The process is set forth in a document released by the European council: http://www.consilium.europa.eu/en/press/press-releases/2017/06/22-euco-agencies-relocation/
In accordance with the agreed procedure all bids need to be submitted by 31 July 2017. The Commission will assess the submissions in light of agreed criteria and this assessment will inform Member States in their decision making through a vote expected in November 2017. The criteria are based on criteria for the decision on the location of a seat for an EU agency and take into account the unique circumstance that the agencies in question already exist. They include: the assurance that the agency can be set up on site and take up its functions by the date the UK leaves the EU, accessibility of the location, existence of adequate education facilities for the children of agency staff, appropriate access to the labour market, social security and medical care for both children and spouses, business continuity and geographical spread.