Citadel Clears $2B Bitcoin Miner Overhang, Ken Griffin Says Seller Nearly Finished

Citadel has unwound more than 80% of the risk it absorbed from a $1.99 billion Bitcoin miner portfolio, removing the seller that pressed on mining stocks for roughly three weeks. Traders had spent that window watching miner names grind lower under pressure that appeared indifferent to valuation. In a letter to clients on Friday, Ken Griffin said that seller is nearly finished, and the firm has already distributed most of the book. The unwind traces back to July 30, when Citadel accepted about $10 billion of stock from Leopold Aschenbrenner's Situational Awareness portfolio after that fund, a four-times-levered AI vehicle, lost 67% in a single month. The 13F, the quarterly holdings report that large investors must file with the SEC, covered the period through June 30 and was lodged on August 14; it listed a $20.24 billion portfolio across just 26 positions, and Bitcoin miners made up $1.99 billion of it. Core Scientific was the largest miner holding at $666 million; Riot Platforms held $468 million, IREN $433 million and CleanSpark $179 million. A fresh $152 million stake sat in Keel Infrastructure, the company Bitfarms became after its April rebrand. The miner books had grown fast, climbing 79% in one quarter while shrinking to under 10% of the portfolio; Riot alone rose 229%. Citadel pushed through nearly 100 block trades worth more than $4 billion to distribute the risk, including the largest intraday blocks of the year in ten separate names, and three Citadel funds gained sharply after the purchase. In the same letter, Griffin described the ability to distribute that risk as central to the investment thesis. A large seller with no reason to care about the price has therefore been replaced by buyers who made the same bet at a lower price. For holders of public mining stocks, the overhang that had functioned like a one-sided bear market for three weeks has mostly lifted.

The episode is a case study in how an artificial-intelligence trade became Bitcoin mining's problem. Situational Awareness, run by former OpenAI researcher Aschenbrenner, had returned 439% in the first half of 2026 before July erased those gains. Aschenbrenner was not buying Bitcoin directly; he was buying megawatts, because public miners already controlled grid capacity and power contracts, making their shares a proxy for AI data-center expansion. The fund bought miners fast and memory chips even faster, according to the 13F's quarter-over-quarter changes. The fund's March positioning showed $8.5 billion of put options against Nvidia, Oracle, Broadcom and other AI names; those puts were the hedge. By June 30, however, the hedges had almost completely disappeared, replaced by $12.5 billion of outright long bets. Sandisk and Micron alone accounted for 55.6% of the entire book, a concentration that left the portfolio exposed to a single semiconductor trade. The portfolio had therefore stopped protecting itself and doubled down on the memory-chip cycle at four times leverage. When chip stocks slid in July, nothing cushioned the fall, and miner exposure — which had grown in dollar terms while shrinking to less than 10% of the portfolio — became collateral damage in a semiconductor deleveraging. The SEC filing makes that sequence visible: the same document that shows $1.99 billion of ASIC mining stocks also shows a book overwhelmingly concentrated in memory names. Citadel's three-week cleanup, executed through block trades rather than exchange dumps, was the mechanism that broke the logjam. Now that the forced seller is mostly gone, the sector can return to its own numbers, from hosting agreements such as Riot's lease with Anthropic to heavy quarterly mining losses. The question left open is whether the buyers who absorbed Citadel's blocks share Aschenbrenner's original thesis that hashrate is a claim on power — at a lower price.

Both threads point to the same conclusion: the $2 billion overhang was a portfolio-construction artifact, not a verdict on Bitcoin. The SEC 13F filing we examined shows miner positions were never a standalone directional call; they were a sub-10% slice of a leveraged AI-chip book that had lost its hedges. Citadel's official client communication confirmed that more than 80% of the aggregate risk has already been distributed. Spot data shows Bitcoin up 6.4% in the last 24 hours, reinforcing the sense that liquidation-driven pressure has passed. For now, the tape is in the hands of long-term holders and the market's own fundamentals.