Ask HN: Anyone know what this DNS TXT record is?

There are two DNS TXT records for example.com, one is an SPF record but I can't find out anything about the other one:

$ dig example.com TXT +short

"v=spf1 -all"

"$Id: example.com 4415 2015-08-24 20:12:23Z davids $"

Does anyone know what the second TXT record relates to?

Thanks,

Elliott