In the last 5 runnings, 3 horses who hit the board in the Blue Grass haev gone on to win grade ones. Peace Rules, Offlee Wild, and Harlans Holiday.

In the last 5 runnnings of the ARk Derby, off the top of my head I can list Flower Alley, Purge, Smarty Jones, and Aflet Alex.
I'll check and see if there were anymore.