OBS_VALUE: The relevant EU law governing slots has been interpreted by the EU Commission as not restricting secondary trading. See page 6, point 5 of the following Communication from the EU Commission: http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2008:0227:FIN:EN:PDF. The Commission has appointed Airport Coordination Ltd, a UK company based at Heathrow, to act as coordinator. ACL allows slot trading. (https://www.acl-uk.org/airport-info-details/?aid=7).