@PraxisOfEvil yes "hedge" funds

https://www.afr.com/markets/debt-markets/the-us800b-hedge-fund-bond-trade-is-unwinding-with-devastating-effect-20250409-p5lqc8

>But another more intriguing and potentially worrying explanation is that the spike in yields was driven by a mass liquidation of highly leveraged hedge fund trades that threatens to destabilise the bond market.

Hedge funds have been engaging in what is known as a basis trade that seeks to take advantage of a modest difference in prices between liquid and easy-to-trade bond futures contracts and the clunkier actual physical bonds that the contracts are tied to.

The traders sell the futures contracts and use an enormous amount of leverage to buy the bonds and amplify the return so it’s worthwhile.

Apollo chief economist Torsten Slok estimates the size of the basis trade to be about $US800 billion ($1.3trn, accounting for a large slice of the $US2 trillion of prime brokerage balances, or loans extended by brokers to hedge funds.

“In the basis trade, hedge funds put on leveraged bets, sometimes up to 100 times, with the goal of profiting from the convergence between the futures price and the bond price, as the futures contract approaches expiry.”