Marcus Chen
Senior Market Analyst
Senior Market Analyst at 13F Insight. Covers institutional portfolio strategy, 13F filings, and smart money trends.
A note from Marcus
Hi, I'm Marcus. I spent six years on the buy side staring at 13F filings for a hedge fund, and the thing that bothered me most wasn't the work — it was knowing that the average investor never gets to see what I was looking at, even though it's all public.
That's why I'm here. Every research piece you'll see under my name comes from real SEC data, run through real institutional logic, and translated into something you can actually act on. I write long when the data deserves it and short when it doesn't.
If you ever spot a number that looks off, email me. I'd rather be corrected than wrong.
Articles by Marcus Chen (542)
- Research
CalPERS Put $19.81B in a Single ETF: Inside America's Largest Pension Fund's Q4 2025 Concentration Play
CalPERS' latest 13F reveals $174.90B in reported AUM with VOO at 11.89% — nearly $20B in one S&P 500 ETF. Combined with NVDA at 8.55%, the top-2 holdings account for 20.44% of this pension giant's portfolio.
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Millennium Management's $237.79B Q4 2025 13F: ETF-Heavy Hedging, WMT +679%, and a $1.83B Bitcoin Bet
Israel Englander's multi-strategy giant allocated $34.15B to broad ETFs (IWM, IVV, QQQ, SPY) — the signature of pod-based beta hedging — while making outsized bets on WMT (+679% shares) and Bitcoin via IBIT.
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Arrowstreet Capital's $170B Quant Machine Cut Apple 38% and Doubled Google: Inside Q4 2025's Biggest Factor Rotation
Arrowstreet Capital's systematic models triggered one of Q4 2025's most aggressive Apple trims (-38% shares) while more than doubling Google. With 93 new positions and $170.74B in 13F assets, here's what the quant signals are saying.
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MFS's $310B Shrinking Empire: America's Oldest Fund Dumps Growth Stalwarts, Loads Up on NFLX (+431%) and SNOW (+446%)
Massachusetts Financial Services has seen AUM decline from $334B to $310B over 8 quarters — yet the 100-year-old fund is making its most aggressive portfolio rotation in years, slashing DXCM (-86%), TEAM (-80%), and VEEV (-78%) while piling into streaming and cloud.
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UBS AM Q4 2025: $472B Giant Pushes NVDA to 8.13% — Highest Among Top-20 Global Filers
UBS Asset Management's $472.97B portfolio reveals aggressive mega-cap tech concentration with NVDA at 8.13% weight, a $2.2B real estate exit from PLD and EQIX, and a staggering +1,064% increase in Netflix shares.
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Janus Henderson's $223B Portfolio Churned 134 Positions in Q4 2025: Inside the Biotech Pivot
Janus Henderson (WhaleScore 75.50) opened 67 new positions while exiting 67 in Q4 2025 — a 13.4% turnover rate signaling active repositioning. New biotech/med-device bets (ISRG, GPCR, PTGX) hint at a healthcare conviction thesis.
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Deutsche Bank's $307B US Equity Book: Trimming Big Tech Winners, Loading NFLX +968%
Deutsche Bank AG's Q4 2025 13F reveals a systematic rebalancing at $307B AUM — cutting GOOGL (-14%), META (-11%), and AVGO (-10%) while loading Netflix shares by 968% and ServiceNow by 386%.
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IMC-Chicago Q4 2025: $275.42B With 84 New Positions and a Derivatives-Led Core
IMC-Chicago filed a $275.42B Q4 2025 13F showing 84 new positions, 84 exits, and a book dominated by ETF, index, and derivative-style exposures.
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CTC LLC Q4 2025: Inside a $204.89B Options Market Maker's 13F Filing
CTC LLC filed Q4 2025 with $204.89B in reported 13F value. But CTC is a Chicago-based options market maker — its holdings reflect hedging and trading inventory, not traditional investment conviction.
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AQR Capital Management Q4 2025: $190.63B After a 21.2% Jump and 69 New Positions
AQR Capital Management ended Q4 2025 with a $190.63B 13F, a 21.2% quarter-over-quarter jump in visible holdings value, and 69 new positions.
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MUFG Financial Group Q4 2025: $66.94B 13F Book in a Single Position
MITSUBISHI UFJ FINANCIAL GROUP disclosed a one-line Q4 2025 13F portfolio worth $66.94B, fully allocated to MS.
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Fisher Asset Management Q4 2025: $292.99B AUM With IEF as #3 Holding
Fisher Asset Management reported $292.99B in Q4 2025 13F AUM, combining mega-cap equities with a large IEF allocation.
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Barclays Q4 2025: $416.70B AUM With SPY at 18.7%
Barclays reported $416.70B in Q4 2025 13F AUM, with SPY alone at 18.7% and top-five concentration near 35%.
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Geode Capital Q4 2025: $1.62T AUM With 27.0% in Top Five Holdings
Geode Capital reported $1.62T in Q4 2025 13F AUM, with NVDA, AAPL, and MSFT leading a 27.0% top-five concentration profile.
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Morgan Stanley’s Q4 2025 13F: The Most Diversified Mega-Filer, With AAPL Still Ahead of NVDA
Morgan Stanley reported $1.67T in Q4 2025 13F AUM with just 18.8% in its top five holdings, highlighting one of the broadest mega-filer books while still keeping AAPL ahead of NVDA.
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FMR LLC's Q4 2025 13F: The Most Concentrated NVDA Bet Among Mega-Filers
FMR LLC closed 2025Q4 with $1.96T in reported 13F AUM, 500 positions, and a 10.29% stake in NVDA ($181.10B), the sharpest single-stock concentration among mega-filers.
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BlackRock’s Q4 2025 13F: A $5.92T Empire Led by NVDA, with IVV Inside the Top 15
BlackRock reported $5.92T in 13F AUM for 2025Q4 across 500 positions, with NVDA as the top holding at $362.80B (7.13%). The top five positions account for 25.1%, while IVV appears as the firm’s #13 position, highlighting its ETF ecosystem scale.
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State Street’s Q4 2025 13F at $2.98T: Custodian Scale Meets Steady Compounding
STATE STREET CORP reported $2.98T in Q4 2025 13F AUM with 500 positions. The filing shows a 65% rise from $1.80T in 2023Q3, led by mega-cap exposures and a top-5 concentration of 24.3%.
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Vanguard's Q4 2025 13F: World's Largest Manager Reaches $6.90T With NVDA as Top Holding
Vanguard Group's Q4 2025 13F shows $6.90T in reported AUM, 500 positions, and NVDA as its largest disclosed position at 6.92% ($422.74B).
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UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC's $472.97B 2025Q4 Build Opened 38 New Positions
UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC reported $472.97B for 2025Q4, with NVDA at 8.13% and top-5 concentration at 27.42%.