third-party source
A post sourced from any site other than the original artist or (official) source provider. This includes instances of official art and game CG that are reuploaded elsewhere online.
Typically, this is a post sourced to another imageboard, booru, or wiki, rather than to the original artist.
This tag can also be applied if a post is sourced from an account who steals and reposts drawings from other artists, whether intentional or unintentional. Heed caution when uploading posts from potential art thieves.