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

Results forspf.optus.bank

Resolver

Location

TXT

Name	TTL	Value
spf.optus.bank	3600	v=spf1 ip4:199.30.234.56/29 ip4:74.203.184.208/30 ip4:199.30.234.64/26 ip4:199.30.234.192/27 ip4:74.203.184.32/27 ip4:207.195.176.0/20 ip4:199.30.235.11 ip4:74.203.185.12 ip4:209.34.255.250 ip4:209.34.255.251 ip4:128.136.104.250 ip4:44.214.246.148 ip4:74. 125.0.0/16 ip4:173.194.0.0/17 ip4:209.85.128.0/17 ip4:216.58.192.0/19 ip4:216.239.32.0/19 ~all