Veteran metals trader Sonny McNess, who previously roiled the London Metal Exchange (LME) with aggressive bets in the aluminum market, is now the chief metals derivatives trader at Hartree Partners LP. In recent weeks, he has heavily bought LME October copper contracts while shorting November futures. This move is a bet that a short-term supply squeeze, should Donald Trump announce tariffs on refined copper, will drive up the premium for near-month contracts. As a result, the October contract briefly traded at a premium of up to $91.99 per ton over the November contract. The LME stated it has mechanisms in place to address the risk of price distortions from large positions.