WG-59 has published ED-133 “Flight Object Interoperabilty” in 2009. Based on experience acquired during the implementation of this specification and driven by requirements in the scope of the Pilot Common Project (PCP), WG-59 was reactivated to produce Revision A of ED-133. Because of technical and interoperability issues it was decided that further validation work is required in order to develop a stable set of technical and operational requirements. These validation activities are currently carried out under the lead of the SESAR Joint Undertaking (SJU). It is expected that the results of this validation will be used by WG-59 for the update of ED-133 starting in the course of 2020.