Leopold Aschenbrenner

persona · active · confidence: medium · reviewed 2026-09-21 · tier: quarterly

Who he is

Affiliation: Founder and portfolio manager, Situational Awareness LP (AI-focused hedge fund, launched 2024 with a reported ~$225M). Role check run 2026-09-21: still running the fund — but not the fund the May file described. H1 2026 +439% net (investor letter reviewed by the FT, 2026-07-24); July 2026 −67% at up to ~4x leverage (borrowed money multiplying the bets); the entire public stock book sold to Citadel in one block before the open on 2026-07-30 (Reuters). About $10B remains, a third to a half of it one private Anthropic stake. To investors: "We let you down this month … I take full responsibility," and the public book will now run "on a fully-paid-for basis" (letter via Business Insider, 2026-07-31). JPMorgan cut off lending (FT, 2026-09-11); Clear Street is the new prime broker (the bank that lends a fund money and holds its stock); back in the market via fully-paid flex options since 2026-09-02 (CNBC, 2026-09-11). Previously OpenAI Superalignment (2023–2024-04, fired — he says over a security memo, OpenAI says a leak); FTX Future Fund (2022); Columbia valedictorian (2021). Married Avital Balwit, chief of staff to Anthropic CEO Dario Amodei, the weekend of 2026-08-01 (Fortune). Age ~24–25.
One-line position: unchanged in words — AGI plausibly by 2027, an intelligence explosion within ~2 years, and the only safe path is a US-government-led national project that out-builds and out-secures China. But he has said nothing in public since 2024-06-14. Filings and two leaked letters are the only new evidence, and they say: still all-in on the physical layer, now without borrowed money.

Discipline & technical bet

AGI forecaster who treats progress as a trendline — count the OOMs (orders of magnitude, 10x steps) and extrapolate — turned concentrated, formerly leveraged AI-infrastructure fund manager. The wager: effective compute (~0.5 OOM/yr physical + ~0.5 OOM/yr algorithmic + "unhobbling") keeps compounding, so the binding physical constraint migrates down the stack — chips → power → (per the Q2 2026 book) memory and storage — and value migrates with it. The fund is that wager as capital: Q2 2026 book $20.24B across 26 names (13F-HR, period 2026-06-30, accession 0000935836-26-000418, cover page verified this cycle), 56% in SanDisk + Micron, the Q1 $8.46B semiconductor put book closed; private stakes in Anthropic (~20% of the fund, bought ~Mar 2025 at ~$61.5B valuation, WSJ), MatX (co-led the $500M Series B, 2026-02-24) and Fluidstack. July proved the thesis at 4x cannot survive a one-month 29–47% drop in memory names plus a software-short squeeze. September shows the same names re-bought unlevered (AMD, Bloom Energy, CoreWeave, SK Hynix, SanDisk, a memory ETF) plus a 21.1% stake in SharonAI Holdings (SHAZ), $523.9M cost, on a Schedule 13D (filed when you own more than 5% and might act; event 2026-08-27), topped up by warrant exercise (13D/A + Form 4, 2026-09-17). Says and Does still point the same way; only the leverage changed.

Key claims (Says)

Notable predictions — with falsifiable checks

Revealed behavior (Does)

Feels

Certainty plus a wound. The OpenAI firing and the FTX collapse ("incredibly tough") taught him institutions fail people; the fund was built so no institution could stop him, and July taught him leverage can. "We came closer to permanent capital impairment than is acceptable to us" is the most self-aware sentence he has published. Wants to be true: the OOM line is destiny and July was noise.

Hears

An EA-forecasting inner circle (Shulman; Cotra-adjacent timelines), his LPs (the Collisons; Gross and Friedman, both now inside Meta's superintelligence push; Jane Street), Anthropic through his wife's office, and the prime-broker and short-seller loop he now blames. No policy world since 2024; no press he answers.

Sees

Where the physical constraint binds next, before the market — power in 2024, memory in 2026 — plus frontier-lab economics from the inside (OpenAI) and the household (Anthropic). What he did not see: a 4x book in illiquid mid-caps is the constraint that binds first.

Incentive map

Re-derived this cycle: maximal and now asymmetric. A ~$10B fund with a third to a half in one private Anthropic position (IPO expected October 2026, TechCrunch); a spouse who is chief of staff to Anthropic's CEO (engaged by 2025-10, married 2026-08); LPs who include two Meta superintelligence executives; prime-broker access on probation (JPMorgan out, Morgan Stanley declined at launch, Clear Street in). He cannot say: Anthropic is overvalued; the intelligence explosion is slipping; memory and power are not the bottleneck; leverage was the thesis. The essay predated the fund and its technical half has scored well on independent cards — moderate discount there. On anything Anthropic-, memory- or timeline-related the discount is maximal. His letters are now the only channel for his views, and letters exist to keep capital in the fund. Rule-25 weight: coincidence discount on every forecast his book is long.

Theories aligned with

What he's reacting against

Where he overlaps / splits (with Rich)

Track record

Empirical vs normative

Weak spots / open questions

Rich's take

Delta log

2026-09-21 — v1→v2 migration + validation (bulk run)

Sources

migrated v1→v2 2026-09-21 · backup: _archives/leopold-aschenbrenner.html.bak-20260921 · converts-from: people/leopold-aschenbrenner.md · AI & Society domain