"On the same day, FINRA, evidently aware there were potential problems with clearing and settlement, imposed a U3 halt. The regulator lifted the halt after ten trading days, but by then the damage had been done: CRGP had lost compliance with SEC Rule 15c2-11, and so reopened on the Grey Market, where it still trades today" https://www.securitieslawyer101.com/2017/calissio-resources-cor-clearing/