StockDriftsWhere conviction is rising: platforms, plumbing, and scale AI
The biggest buys cluster around two themes: AI platforms and the hardware/software plumbing that feeds them. Jane Street is paying up for scale, but in names where unit economics and moats are already proven.
On the platform side, they aggressively added to:
- AMZN (up +225.8% in shares, now 2.17% of the book), a clean bet on cloud and retail operating leverage.
- NVDA (+875.9%) and MSFT (+3318.2%), turning prior “toe-hold” positions into core AI exposures rather than momentum trades.
- META (+703.0%) and GOOG (+30.0%), rounding out a full-stack data, ad, and AI platform basket.
In the AI plumbing and storage complex, they’re clearly reloading, not exiting:
- STX (+7380.5%) and WDC (+2949.5%) as second-derivative AI data storage winners, after taking profits in earlier memory leaders.
- INTC (+1676.7%), AMD (+354.7%), TXN (+3441.3%), LSCC (+59.3%), SMTC (+333.6%), and TSEM (+146.0%) — a broad, diversified semi toolkit spanning CPUs, accelerators, mixed-signal, and specialty foundry.
- PANW (+3002.6%) and FTNT (+2769.3%), marrying AI’s compute build-out with the security spend that inevitably follows.
They’re also scaling software and tools around this stack. INTU (+13325.6%), ORCL (+60.5%), PLTR (still sizable despite a modest trim), and CRWV (+56.8%) point to conviction that data and automation will monetize as fast as GPUs ship. The common thread: they’re not guessing the next AI winner; they’re buying the rails.
Conviction
The big buys
The biggest dollar adds this quarter — where conviction is rising.
| Position | Change | Portfolio weight | Value |
|---|---|---|---|
| SPYSTATE STR SPDR S&P 500 ETF T | Added 118.1%+$17.90B | 21.0% | $33.05B |
| AMZNAMAZON COM INC | Added 225.8%+$2.36B | 2.2% | $3.41B |
| NVDANVIDIA CORPORATION | Added 875.9%+$2.12B | 1.5% | $2.36B |
| MSFTMICROSOFT CORP | Added 3318.2%+$1.61B | 1.1% | $1.66B |
| STXSEAGATE TECHNOLOGY HLDNGS PL | Added 7380.5%+$1.40B | 0.9% | $1.42B |
| METAMETA PLATFORMS INC | Added 703.0%+$1.12B | 0.8% | $1.28B |
| CSCOCISCO SYS INC | Added 4513.6%+$1.07B | 0.7% | $1.09B |
| INTCINTEL CORP | Added 1676.7%+$963.6M | 0.7% | $1.02B |
Dollar changes estimated at current prices (shares added × current price); top-50 current positions only.
What they are harvesting: memory, decarbonization, and small-cap beta
If the buy tape is about building a durable AI stack, the sell tape is a profit-taking manual. Jane Street is locking in extraordinary gains where the risk/reward has flipped.
The most telling moves:
- MU (shares down -60.7%) and SNDK (-35.2%) were cut hard after gain_vs_avg_buy_pct of 727.3% and 565.2%, respectively. That’s not a change of mind on memory; it’s classic “harvest the bubble” behavior.
- DELL (-62.0%) and CLS (-17.1%) trims show them easing off PC/servers and contract hardware after a powerful run, while rotating into more diversified infrastructure like STX, WDC, and SMCI.
- BE (-15.3%) marks a broader retreat from speculative decarbonization hardware. With Energy exposure dropping from 3.81% to 1.6%, BE looks like a funding source, not a thesis centerpiece.
On the macro and factor side, IWM (shares -23.6%) and SPDW (-19.4%) are being scaled back, even as SPY, QQQ (+56.8%), IEMG (+127.4%), and VXUS (+6893.1%) are ramped. That’s a clear message: less small-cap and ex-US scattershot, more liquid, benchmark-friendly exposure around a concentrated set of active bets.
Even PLTR (-8.8%) and C (-7.4%) trims fit this pattern — monetizing winners at double-digit gains while keeping the core of each theme intact.
Sector exposure: tech still rules, but beta and real-economy themes are catching up
Technology is still the engine of this book at 33.27%, but its share is actually down from 38.34%. What’s changed isn’t their belief in tech, but how they’re expressing it: fewer concentrated moonshots, more diversified exposure wrapped in indices and broad semi/software baskets.
The most striking shift is the jump in unclassified ETF and macro exposure from 48.53% to 50.58%. SPY at 21.04% is the anchor, complemented by QQQ, IEMG, VXUS, TLT (+390.9% in shares), IBIT (+323.7%), and a resized IWM/ SP DW pair. This is beta as ballast, giving them room to run concentrated in AI and infra without blowing up tracking error.
Under the hood, sector rotation is subtle but telling:
- Consumer Discretionary climbs from 3.43% to 5.89% via AMZN, HLT (+612.3%), and ORLY (+185.1%) — a bet on high-quality consumer names with pricing power rather than broad retail.
- Industrials jumps from 0.9% to 2.43% as HWM (+116.1%), STRL (+10129.6%), and PWR (+6949.7%) build an infrastructure sleeve tied to aerospace, grid, and construction.
- Health Care edges up from 2.71% to 3.01% through UNH, MCK (+825.4%), LLY (+295.6%), and BSX (+199.8%), a quiet but clear nod to structural growth outside tech.
- Energy and Finance both shrink, with BE and C/RIOT mix showing they prefer growth and infrastructure over traditional cyclicals.
What this quarter’s repositioning telegraphs for Jane Street’s playbook
Jane Street’s 41.13% performance in 2026 Q2 isn’t leading them to swing harder at the fences. Instead, they’re using the win to reshape the playbook toward scalable, liquid expressions of long-duration themes.
Going forward, expect three pillars to define their stance. First, a large SPY and ETF core that keeps overall volatility and tracking error in check. Second, a rebuilt AI complex centered on platform megacaps, a diversified semi stack, storage, and cybersecurity — names like NVDA, MSFT, AMZN, META, STX, WDC, PANW, and FTNT doing the heavy lifting. Third, incremental growth in real-economy and defensive engines: infrastructure (HWM, STRL, PWR), high-quality consumer (HLT, ORLY), and health care (UNH, MCK, LLY, BSX).
The trims in MU, SNDK, DELL, BE, and small-cap ETFs show a disciplined willingness to step away once a trade migrates from mispricing to consensus. The notable adds to TLT and IBIT, even at small losses vs cost, suggest they still want optionality around rates and digital assets, but strictly as satellite exposures.
In short, this isn’t a fund bailing on AI; it’s one graduating from speculative AI trades to owning the infrastructure and platforms that should compound through multiple cycles.
Rotation
How the book's themes shifted
Portfolio weight by theme, this quarter versus last.
Frequently asked questions
What did Jane Street Group LLC buy most aggressively in 2026 Q2?+
In 2026 Q2, Jane Street Group LLC’s biggest add by dollars was SPY, which rose to 21.04% of the portfolio after a +118.1% increase in shares. They also made large buys in AMZN, NVDA, MSFT, and a range of semiconductor, software, and infrastructure names.
What is Jane Street Group LLC's biggest holding as of 2026 Q2?+
As of the 2026 Q2 13F, Jane Street Group LLC’s largest disclosed position is SPY at 21.04% of the reported portfolio, dwarfing all single-stock holdings such as AMZN and NVDA.
How is Jane Street Group LLC positioned toward AI and semiconductors?+
Jane Street remains heavily exposed to AI and semis through large positions in NVDA, MSFT, AMD, INTC, TXN, LSCC, SMTC, and others, but has trimmed earlier outsized winners like MU and SNDK. The focus is shifting from narrow memory bets to a broader, infrastructure-style AI stack.
Which sectors did Jane Street Group LLC reduce in 2026 Q2?+
They reduced exposure to Technology in percentage terms (though it remains the largest sector), Energy, Finance, and small-cap and international beta via names like BE, C, MU, SNDK, IWM, and SPDW. Proceeds helped fund larger positions in SPY, AI platforms, infrastructure, and health care.
Did Jane Street Group LLC change its use of ETFs in 2026 Q2?+
Yes. ETF and unclassified exposure grew to 50.58% of the reported book, with SPY, QQQ, IEMG, VXUS, IBIT, and TLT all seeing big share increases, while IWM and SPDW were trimmed. This indicates a stronger reliance on broad beta and macro tools alongside their stock-specific themes.
How did Jane Street Group LLC's sector allocation shift toward Industrials and Health Care?+
Industrials rose from 0.9% to 2.43% on large adds to HWM, STRL, and PWR, signaling conviction in aerospace and infrastructure. Health Care increased from 2.71% to 3.01% via expansions in UNH, MCK, LLY, and BSX, adding a resilient growth and defensiveness layer outside of Technology.