A London-based trading house bought 250,000 barrels of oil during the historic plunge below $0 and likely made a fortune

One trader bought 250,000 barrels of oil and secured a rare payout as oil prices turned negative last month, causing jitters in markets and leaving most other traders scrambling to find storage options across both sides of the Atlantic, Bloomberg reported on Thursday.

But for BB Energy, a trading house based in London, the historic oil-market crash was a golden opportunity because it had storage capacity when other firms didn’t, a source told Bloomberg. BB Energy bought about 10% of all barrels of West Texas Intermediate crude futures for delivery in May.