What other parties may voluntarily participate in Air AMS?

What other parties may voluntarily participate in Air AMS?

The information supplied by the incoming carrier may be supplemented by additional information provided by four other eligible parties including the:
  
1. Automated Broker Interface (ABI) Filer (importer or customs broker)
2. Container Freight Station (CFS)
3. Express Consignment Carrier Facility (ECCF)
4. Air carrier that arranged to have the incoming air carrier transport the cargo to the United States.