AMBest Carrier Settings
The ratings come from AMBest, as illustrated by the logo on the Policy tab.

You can hover your mouse over the logo to get the information in a floating tooltip.

Or click the logo to get it in a small popup that you can copy/paste from.

The update frequency (quarterly) and last update date are indicated at the bottom, for example:
ClariNet LS updates AMBest data once per quarter. The last update was on 01/08/2019.
The current list of valid NAIC Company Numbers and Carrier names to use on the Policy tab, Carrier field and in the Excel Uploader (or xml) is available to download from the Help/Templates menu item.