1. 8x8 Inc.
2. AT&T Inc.
3. AVOXI Inc.
4. Bandwidth Inc.
5. British Telecommunications PLC
6. Cisco Systems Inc.
7. Colt Technology Services Group Limited
8. DID Logic
9. Flowroute by Intrado Life & Safety Inc.
10. Fusion Connect Inc.
11. GTT Communications Inc.
12. IntelePeer
13. International Business Machines Corporation
14. Lumen Technologies Inc.
15. Mitel Networks Corporation
16. Net2Phone Global Services
LLC by IDT Corporation
17. Nextiva Inc.
18. Plivo Inc.
19. Rogers Communications Inc.
20. Tata Communications Limited
21. Telstra Group Limited
22. Twilio Inc.
23. Verizon Communications Inc.
24. Vodafone Group PLC
25. Vonage Holdings Corp. by Telefonaktiebolaget LM Ericsson