From the website:
Empire City Subway Company ECS is a wholly owned subsidiary of Verizon specialing in subsurface engineering and construction services. Since 1891, ECS has held a franchise from the City of New York to build and maintain a conduit and manhole infrastructure in Manhattan and the Bronx in which it rents space to telecommunications and cable television service providers. ECS Also Provides a broad array of services to facilitate the installation, maintenance and protection of underground cables in the greater metropolitan New York City area.