I totally agree with you those speculators are tasting bitter pill made by themselves. Specially, it seems that traders of Bank of China, the biggest loser of -40$, are really morons. They are professional traders and they are clear that they're not able to do the physical delivery, but they made such a huge mistake. They exposed their vulnerable back to their rivals. Even worse, they were selling other postions in a hurry and flurry second day and caused a second earthquake to the market. I'm not blaming NYMEX. Anyway, the game was carrying on under the the public rules.You seem like you’re placing the blame on NYMEX. Retail speculators have the responsibility to: 1. Understand their broker’s last trading day policy and position liquidation policy for the particular instruments they are trading, and 2. Understand the delivery and settlement specifications for the particular instruments they are trading.
What really interests me is how WTI ecosystem, as well as the front-month contract, will be impacted by this negative price. Speculators, merchants, producers, the exchange, all of them are members of this ecosystem. Now that speculators are doubting the pricing authority of WTI and they may step out of this market, how would the exchange reflect?

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