Over the past month, crude oil prices have been inching steadily upward, gaining 20%. Brent crude (BZ) rose from $94 to $114. So crude oil has once again become a hot trading asset in recent markets, with both trading volume and open interest up considerably. The open interest in Brent crude (BZ) on CEXs has surpassed $400 million. However, just like other TradFi markets, trading volume and open interest are now concentrated among a handful of top players. The entire market is at $400 million.