RCLEC (RingCentral's CLEC) does not seem to host the majority of RingCentral's numbers despite being fully capable of doing so, RingCentral seem to sprinkle their numbers across Onvoy & Bandwidth.com if memory serves.

Makes for some really fun port out requests, when a client with 6 numbers has those numbers sprinkled across 3 or 4 different underlying telecoms despite RingCentral generating one unified bill for their service.