Short sellers gain $6 billion as AI debt fears hit neocloud stocks

Short sellers have earned $6 billion in paper profits this month by betting against US neocloud and data center companies, as concerns over debt-fueled AI expansion triggered a selloff. Short interest in firms like CoreWeave and Nebius ranges from 20 to 26 percent of free float. CoreWeave shares fell nearly 30 percent, yielding $1.7 billion in short-seller profits, while Nebius short bets gained $2.94 billion in October despite year-to-date losses. Combined short profits from IREN and Applied Digital exceeded $1.2 billion, with Core Scientific adding $115 million. About $17 billion of stock across the five companies is currently sold short, with borrowing costs remaining low, according to ORTEX data. Short interest has risen since the start of 2026 for several firms.