The irony is that the firm's founder - Stafford Jr., made his fortune trading the VIX. Legendary in fact. His son is/was running the company.
CME is where they went debit so it may have been the VIX that nailed them, but it sounds more like it may have been an ES hedge.
someone correct me if i'm wrong but i believe ronin was a prop firm trading their own funds. no outside money.
No, Ronin was a Direct Clearing Member. It was the Exchange pulling the plug on a Clearing Firm. So by Regulation the CME’s Depository Trust & Clearing House took over the Firm’s portfolio assets and liquidated them via auction. Quickly.