Jane Street lost $15 billion in July and still set a record. Now regulators want to know who financed it
A $15 billion July loss still left the trading firm ahead of its record 2025, and a $14.6 billion bond sale moved its funding toward asset managers. Now the Fed and the Bank of England are asking banks what they are owed by trading firms like it.
Vincent Jiang · 3 min read
A bad month, in the firm's own words
"July was a bad month," Jane Street partner Turner Batty wrote to staff. The ledger beneath the note: about $15 billion lost, the firm's first monthly loss in roughly a decade, as its stake in the AI hedge fund Situational Awareness collapsed and several of the largest memory and semiconductor stocks fell around 50 percent 13. The fund, run by former OpenAI researcher Leopold Aschenbrenner, sold most of its public equities to Citadel after margin calls 12.
Two months later, the questions land
The Federal Reserve and the Bank of England are asking global banks what they lend large trading firms, how that exposure moved intraday, and whether risk controls held 2. The SEC has already subpoenaed Goldman Sachs, JPMorgan, Citigroup and Bank of America over the fund's leverage and the trades that triggered the margin calls 2. One report puts Goldman's financing fees from the fund above $200 million this year, the largest in its hedge-fund prime brokerage; that figure is single-source 8.
The loss that didn't dent the year
By mid-August the firm had booked more than $40 billion of net trading revenue for 2026, past the $39.6 billion record it set for all of 2025 and beyond any Wall Street bank 13. Days later it sold $14.6 billion of bonds across three tranches, with PIMCO, Capital Group and Fidelity buying, to repay floating-rate loans and fund technology infrastructure 3. Funding is shifting from bank desks to asset managers while supervisors question the bank desks.
Now it sells the leverage retail buys
This year the firm also began writing the swaps behind leveraged single-stock ETFs: about $1.2 billion of notional across roughly 75 funds in the second quarter, near 2 percent of a segment Clear Street leads at about 21 percent 4. Goldman Sachs and Nomura each hold around 10 percent 5. Notional is reference exposure, not capital at risk 5.
Clear Street leads single-stock ETF swaps at 21%; Jane Street, new this year, holds 2%
Data
| Value | |
|---|---|
| Clear Street | 21% |
| Marex | 11% |
| Goldman Sachs | 10% |
| Nomura | 10% |
| Jane Street | 2% |
The crack behind a paywall
A Jane Street-leased data center in central Oklahoma was funded with $2.25 billion of five-year green bonds in August, priced to yield almost 9 percent 6. A paywalled report on 20 September says that debt has soured; the detail beneath the headline could not be checked here 7. The Bank of England warned in February that trading firms depend on banks for leverage, clearing and market access, and that intraday counterparty risk had risen "in lockstep" 5.
What to watch
Third-quarter fund filings will show whether that 2 percent share grows 5. If supervisors judge banks too exposed, the tool on the table is more high-quality liquid assets held against those exposures, a cost the banks carry 8. The prop risk left the banks after the last crisis. The financing never left with it 8.
How this brief was made
01Gathered & sourced291 channels · 1,820 articles▾
Agents swept 291 channels and ingested 1,820 articles, then de-duplicated and ranked them for signal.
02Verified & cross-validated8 claims · 33 data feeds▾
Every one of 8 load-bearing claims was checked against primary sources, with 33 live data feeds reconciling the figures and charts.
- 1CNBC (Reuters), Jane Street took $15 billion hit in July tied to Situational Awareness, AI selloff, sources say, 14 August 2026
- 2Reuters (via MSN), US Fed, BoE step up scrutiny of bank exposure to trading firms after Jane Street loss, FT reports, 21 September 2026
- 3Bloomberg via Mint, Jane Street Lost $15 Billion in Its First Down Month in a Decade, 15 August 2026
- 4Bloomberg, Jane Street Joins Wave of Dealers Offering Swaps for Risky ETFs, 20 September 2026
- 5Disruption Banking, Jane Street's $1.2 Billion Single-Stock ETF Swaps: Where Does the Risk Sit?, 23 September 2026
- 6Bloomberg, Jane Street-Tied Data Center Sells $2.25 Billion in Green Bonds, 13 August 2026
- 7The Information, Jane Street-Linked Data Center Debt Sours, 20 September 2026
- 8ZeroHedge (via Alto), Regulators Find Their Situational Awareness: Fed, BoE Probe Bank Exposure To Jane Street After AI Fund Meltdown, 24 September 2026
03Reviewed & edited2 human editors▾
2 editors read the draft against the evidence, tuned the framing, and signed off before it shipped.
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AI-generated from this story and its cited sources. Not investment advice.
