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 (311)
- Research
Gates Foundation Trust Rebuilt to $35.4B in Q4 2025 After a $8B Q3 — BRK/B Still Leads at 27.6%
The Gates Foundation Trust recovered from $8B in Q3 to $35.4B in Q4 2025 across 23 holdings. Berkshire Hathaway remains the top position at 27.6%, Waste Management at 18.0%.
- Research
TCI Fund Management Put 27% of $53.6B Into GE Aerospace in Q4 2025 — a Nine-Stock Portfolio Built on Monopoly Economics
Chris Hohn's TCI Fund Management held just 9 positions worth $53.6B in Q4 2025. GE Aerospace topped the book at 27.3%, followed by Visa at 18.1% and Microsoft at 15.1%.
- Research
Pershing Square Ran $15.5B Through Just 11 Names in Q4 2025 — and Brookfield Led the Way
Bill Ackman's Pershing Square held only 11 positions worth $15.5B at year-end 2025. Brookfield Corp topped the book at 18.1%, followed by Uber at 15.9% and Amazon at 14.3%.
- Research
STATE STREET CORP's Q4 2025 Filing Still Ran Through NVDA, AAPL, and MSFT
STATE STREET CORP looked diversified on the surface in Q4 2025, but NVDA, AAPL, MSFT still anchored the real risk budget. The top five positions reached 22.1% of reported value across 500 fetched lines.
- Research
Amundi's Q4 2025 Filing Keeps a Mega-Cap Core While Quietly Rebuilding the Optionality Sleeve
Amundi's top holdings still read like a global mega-cap core, but the more revealing part of the filing is the new convertible and optionality sleeve around that foundation.
- Research
Nuveen's Q4 2025 Filing Kept a Broad Core but Turned Aggressive on Netflix and ServiceNow
Nuveen still looks like a diversified mega-cap allocator in Q4 2025, but the filing also shows sharper risk-on behavior through outsized Netflix and ServiceNow increases.
- Research
State Street, Northern Trust, and BNY Mellon Show the Custodian-Bank Breadth Spectrum in Q4 2025
State Street, Northern Trust, and Bank of New York Mellon all hold the same mega-cap leaders, but their top-ten concentration ranges from 27.7% to 31.4%.
- Research
Giant Filers Spread Top-Ten Exposure From 26% to 36% in Q4 2025
JPMorgan, Vanguard, Capital World Investors, and FMR all own the market leaders, but their top-ten concentration ranges from 26.3% to 36.4%, creating very different portfolio behavior.
- Research
Legal & General's $451B Q4 Portfolio: NVIDIA and Apple Neck-and-Neck at the Top, a $102B AUM Swing, and Netflix Up 916%
Britain's largest asset manager holds NVIDIA at $32B and Apple at $30B in an unusually close #1/#2 race. AUM crashed $102B between Q3 and Q4 2024, then recovered. Netflix shares surged 916% — the fourth mega-filer to make this trade in Q4.
- Research
Royal Bank of Canada's $615B Q4 Filing Holds 29,036 Positions — Including $12.5B of Its Own Stock and Rival Toronto-Dominion
Canada's largest bank filed a U.S. 13F with 29,036 positions, three S&P 500 ETFs in its top 5, $12.5B of its own stock (RY), and $11.9B of competitor Toronto-Dominion. Netflix shares surged 893% in one quarter.
- Research
Capital International Investors' $638B Portfolio Puts Broadcom at #1 and Built a $2.5B Netflix Position in One Quarter
While most mega-filers lead with NVIDIA, Capital International Investors bets biggest on Broadcom at 7.7% of portfolio. They also increased Netflix shares by 710% in Q4 2025, added $3.4B in TotalEnergies, and exited Disney entirely.
- Research
Dimensional Fund Advisors' $477B Q4 Portfolio: The Factor Investing Pioneer Holds 13,709 Stocks and Not a Single ETF
DFA — the firm that brought academic factor research to real portfolios — files 13,709 positions without a single ETF or index fund. Its Q4 2025 13F reveals a 17.9% top-5 concentration with Berkshire Hathaway, Exxon, and Visa in the top 15 — the anti-momentum portfolio built on Nobel Prize-winning research.
- Research
Wellington Management's $571B Q4 Portfolio: The Stock Picker's Stock Picker Built a $14B Eli Lilly Position While Everyone Else Was Chasing AI
Wellington Management is the largest pure active manager in our database — no ETFs, no index funds. Its Q4 2025 13F reveals a $571B portfolio where healthcare rivals tech for attention: Lilly at $14.4B, Merck at $9.1B, and a Meta trim of 18% that goes against the passive consensus.
- Research
Bank of America's $1.375T Q4 Filing: SPY Cut in Half, NVIDIA Trimmed 22%, and $26B in Vanguard ETFs Nobody Talks About
Bank of America's Q4 2025 13F reveals the last uncovered megabank: a $1.375 trillion portfolio with 28,105 positions, a 12.9% top-5 concentration that makes it the most diversified major bank filing, and a massive Vanguard ETF allocation that signals where Merrill Lynch clients actually park their money.
- Research
Goldman Sachs' $811B Q4 Portfolio Puts Tesla in the Top 5 — Ahead of Alphabet, Amazon, and Meta
Goldman Sachs' Q4 2025 13F reveals an $811B portfolio where Tesla at $18.3B ranks #5 — above Alphabet, Amazon, and Meta. NVIDIA leads at $41.8B, but the real story is Goldman's $28.4B SPY position and what the flat QoQ growth signals.
- Research
Fidelity's $1.96 Trillion Q4 Portfolio: Trimming Meta by $4.3 Billion While Doubling Down on Alphabet
FMR LLC's Q4 2025 13F reveals a $1.96T portfolio across 5,359 positions. The world's third-largest asset manager cut Meta by $4.3B and NVIDIA by $2.8B — but added $5.3B to Alphabet's two share classes. Here's what the rotation signals.
- News
How Zoom's CEO Sells 12,100 Shares Every Single Day — and Why It Hasn't Stopped
Eric Yuan has filed 1,506 Form 4 transactions since Zoom's 2019 IPO — converting and selling shares on a daily mechanical schedule. Career total: $1.3B sold, zero bought. He also quietly sits on the Intuit board.
- News
Carl Icahn Has $2.6B in IEP Unit Transfers Since 2003. The SEC Wanted to Know Why.
The legendary activist investor settled SEC charges over undisclosed pledges of Icahn Enterprises units — while the stock fell 85% from its peak. A breakdown of 410 transactions across 25 companies.
- Research
Norway's $935B Sovereign Wealth Fund Put $62B in NVIDIA Alone: Inside Norges Bank's Q4 2025 US Equity Portfolio
Norges Bank Investment Management, managing the world's largest sovereign wealth fund, disclosed $935B in US equities for Q4 2025 — a 7.4% QoQ increase. NVIDIA leads at $62B (6.7% of portfolio), followed by Apple at $52B and Microsoft at $51B.
- Research
Insider Cluster Buying: A Signal Framework for Retail Investors
A practical framework for identifying high-signal insider cluster buying events and filtering out low-information Form 4 noise.