[clbrmbr]

The folks who run the public NTP pool really ought not to make it easier to pay them money to use it commercially.

I submitted a request for commercial use via their online form but never received a response.

[homebrewer]

It's mostly run by one guy with very limited time. On their forum, I've seen one vendor repeatedly asking for the vendor prefix for three years, only getting the response once, and never actually receiving the prefix.