It can be anything! An apex, subdomain, or even a URL.

Results forauth.call.3layer.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2023-03-11T07:05:02.965	2023-03-11T07:05:02	2023-05-08T14:00:28	3layer.com	auth.call.3layer.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2
2022-03-09T22:08:23.399	2022-03-09T22:08:19	2023-04-10T22:08:19	3layer.com	auth.call.3layer.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2
2021-03-09T16:00:44.96	2021-03-09T16:00:43	2022-04-10T16:00:43	3layer.com	auth.call.3layer.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2
2020-06-01T11:50:20.284	2020-05-08T14:14:24	2021-05-08T14:00:28	3layer.com	auth.call.3layer.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2
2020-05-08T14:14:25.414	2020-05-08T14:14:24	2021-05-08T14:00:28	3layer.com	auth.call.3layer.com	C=US, ST=Arizona, L=Scottsdale, O="GoDaddy.com, Inc.", OU=http://certs.godaddy.com/repository/, CN=Go Daddy Secure Certificate Authority - G2