Space Infrastructure Servicing

Space Infrastructure Servicing (SIS) is a spacecraft concept being developed by Canadian aerospace firm MDA to operate as a small-scale in-space refueling depot for communication satellites in geosynchronous orbit. In June 2017, SSL (MDA's Palo Alto, California company) announced its first commercial customer, Luxembourg-based satellite owner / operator SES S.A. Maxar acquired SSL, then in 2019, SSL abandoned the SSP project.

Source: Wikipedia — Space Infrastructure Servicing (CC BY-SA 4.0)