Who owns that IP? The ranges providers publish themselves.
Seventeen providers publish the address ranges they use. We fetch each list daily, keep a log of what changed, and use them to flag hosting and crawler addresses in the Truth Check.
Short answer
Each provider’s own file is the source; we show its timestamp where it has one. These lists are published for customers to allowlist traffic and carry no licence, so we cite them and imply no affiliation.
Have an address and want to know whose it is? Look it up; the lookup checks every list above.