We'll have $20 Oil tomorrow with the June contract. In terms of the May contract meltdown - my GUESS is that some retail longs were autoliquidated by brokers. Commercials who were short and planning on making delivery offset some at ridiculous price levels. Just a guess but I think it's a good one.
This is why I'm putting a limit order to cover June at 0.01. There's no telling what will happen if you cover in the negatives. The system might make an error and think you covered for a loss!
I don't think crude has limit downs. If it did, it surely would have hit it that day a month ago when it dropped from 40 to 27.
In contrast, Brent Oil futures behaved with a normal looking steep decline (no negative prices) of only down 2 - 3 points as if nothing was occurring in the Oil markets today. Fascinating...gotta save charts of Light Crude Oil because 10 - 20 years from now...nobody is going to believe that Crude once traded negative prices. wrbtrader