$1.99 billion in Bitcoin miner exposure sat as an invisible ceiling over the sector for three weeks. Five positions in the last Situational Awareness 13F, filed August 14 and covering the period to June 30, account for $1.898 billion of that figure: Core Scientific at $666 million, Riot Platforms at $468 million, IREN at $433 million, CleanSpark at $179 million, and a fresh $152 million stake in Keel Infrastructure, the company Bitfarms became after rebranding in April. On Friday, Ken Griffin told Citadel clients the firm has unwound more than 80% of that risk.
The portfolio that produced it was Situational Awareness, an artificial intelligence-themed fund run by former OpenAI researcher Leopold Aschenbrenner. It gained 439% in the first half of 2026. Then July arrived, chip stocks slid, and a fund running four-to-one leverage lost 67% in a single month. On July 30, Aschenbrenner handed roughly $10 billion of stock to Citadel.
What Aschenbrenner was actually buying
Miners were never the destination. Aschenbrenner was buying megawatts. Miners already held grid capacity; data centers needed it. Miner exposure inside the fund climbed 79% in a single quarter; Riot alone jumped 229%.
The larger bet was memory. The June 30 13F showed $12.5 billion of outright long positions, with Sandisk and Micron accounting for 55.6% of the $20.24 billion book. In March, the same portfolio had held $8.5 billion in put options against Nvidia, Oracle, Broadcom, and other names as hedges. By June 30 those puts were nearly gone. When chips fell, nothing cushioned the drop. Miners were collateral damage in a memory-chip trade.
Citadel's distribution and what's left
Citadel moved quickly after absorbing the book. Nearly 100 block trades worth more than $4 billion went through, including the largest intraday blocks of the year in 10 separate names. Griffin, in a letter Reuters cited, told clients the firm's ability to distribute that risk was central to its investment thesis. Citadel bought the portfolio at a discount; three Citadel funds gained sharply afterward.
With the seller more than 80% cleared, miner stocks are handed back to their own fundamentals: hosting deals such as Riot Platforms' Anthropic lease and heavy quarterly mining losses. $BTC's 7% daily gain lifted Bitcoin to roughly $77,309, taking its market value to approximately $1.55 trillion. The blocks Citadel sold went somewhere. Whoever bought them made the same power-capacity bet Aschenbrenner made, quietly, at a lower price.