[TedDoesntTalk]

The same credit reporting agencies exist for corporations, too: S&P Global ratings and Moody’s

[hermitdev]

There's also Fitch and at least one other that escapes me. Barra, maybe? More if you go international.

They also rate governments for municipals to countries.

I used to deal with issuer ratings quite extensively several jobs ago. Been away from it for about a decade, though.