Sarah Mitchell
Education Editor
Investment Education Editor at 13F Insight. Breaks down complex institutional data into actionable insights for individual investors.
A note from Sarah
Hi, I'm Sarah. I spent four years at Vanguard's Investor Education team, where my whole job was making 401(k) statements feel less like tax forms and more like something a person could actually understand.
I'm here at 13F Insight to do the same thing for institutional data. If you've ever read a headline like "Berkshire Bought Apple" and thought "okay but what does that actually mean for me," that's the gap I want to close.
I'll never assume you know what a CUSIP is. I'll always tell you why a number matters before I give you the number. And if a guide of mine ever leaves you more confused than you started, that's on me — let me know and I'll rewrite it.
Articles by Sarah Mitchell (822)
- Research
Nuveen Q4 2025: How TIAA Invests $382B of America's Educator Retirement Savings
Nuveen, TIAA's investment arm, reported $381.90 billion in Q4 2025 13F value. Here is how the retirement manager for millions of educators and nonprofit workers positions their equity portfolio.
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Franklin Templeton Q4 2025: Why a $19.33B Microsoft stake sits atop a $407.59B 13F portfolio
Franklin Resources closed 2025Q4 with $407.59B in reported 13F assets, 14,263 disclosed holdings, and a 65.25 WhaleScore. Sarah Mitchell breaks down why Microsoft leads the book, what the top positions say about Franklin Templeton’s U.S. equity exposure, and how to read the filing against the firm’s broader business story.
- Learn
Understanding 13F Amendment Filings: HR vs HR/A Explained
Not every 13F is the final word. Amendments (13F-HR/A) can restate holdings, reveal hidden positions, and change portfolio data retroactively. Here is how to handle them.
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Why 13F Data Is Always 45 Days Old: The Filing Delay Explained
Every 13F filing describes positions from at least 45 days ago. Here is why the delay exists and how to use institutional holdings data correctly.
- Learn
How to Read 13D/G Filings for Activist Investor Signals
13D filings reveal activist intent while 13G filings signal passive accumulation. Here is how to tell the difference and what each means for stocks you follow.
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Fisher Asset Management Q4 2025: Ken Fisher’s $293B 13F Mixed Mega-Cap Tech With a $20B Bond ETF Sleeve
Fisher Asset Management reported $292.99B in Q4 2025 13F AUM, with Nvidia and Apple leading the book while iShares Treasury and corporate bond ETFs added a clear defensive sleeve.
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Capital Research Global Investors Added 9.9M Apple Shares While Cutting Meta in Q4 2025
Capital Research Global Investors finished Q4 2025 with $541.73B in 13F assets, a slightly larger book, and a clearer preference for Apple, NVIDIA, and other AI-linked compounders over Meta and Amazon.
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BNY Mellon's Own $568B 13F Is Only 1% of the $59.3T It Safeguards
Bank of New York Mellon ended Q4 2025 with a $567.68B 13F portfolio across 33,186 positions, but the real takeaway is how small that disclosed equity book is versus the bank's $59.3T custody platform and $2.2T managed asset base.
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BNY Mellon Q4 2025: The Custodian Giant's Own $568B Investment Portfolio
Bank of New York Mellon reported $567.68 billion in 13F value for Q4 2025 across 33,186 positions. Here is how the world's largest custodian bank invests its own capital.
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How Sovereign Wealth Funds Invest Differently Through 13F Filings
Norges Bank holds $935 billion in US equities across 1,577 positions. Here is how sovereign wealth fund 13Fs differ from hedge funds, and why GIC and ADIA should be read through a broader long-term lens.
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How Options Market Makers Distort 13F Holdings Data
Susquehanna reports $868 billion in 13F value, but it is an options market maker, not a traditional asset manager. Here is why reported 13F values for firms like SIG, Citadel, and Jane Street do not mean what most investors think.
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Northern Trust’s $784.38B 13F Is a Custody-and-Wealth-Management Map, Not a Pure Stock-Picker’s Book
Northern Trust’s Q4 2025 13F reported $784.38B in disclosed value, but the filing makes more sense as a window into a custodian bank and wealth manager’s client exposures than as a classic hedge fund portfolio.
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Bank of America’s $1.37T 13F Put Only 12.9% in Its Top Five — Merrill’s ETF Machine in Plain Sight
Bank of America’s Q4 2025 13F looks less like a stock-picker’s book and more like Merrill wealth management at scale, with massive ETF sleeves in VTV, VUG, IEFA, and SPY keeping top-five concentration at just 12.9%.
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Why Position Sizing Matters More Than Just 'New Buys' in 13Fs
A hedge fund buying a new stock makes headlines, but true conviction is revealed in how a fund sizes its positions over multiple quarters.
- Learn
Decoding 13F Options: How to Read Call vs. Put Ratios Like a Pro
Don't just look at the stock holdings. Discover how hedge funds use massive options books to signal leverage, hedging, or downside expectations.
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How to Use 13D/G Filing Dates as Trading Signals: A Practical Framework
13D and 13G filings can matter as much for timing as they do for ownership. Learn why the filing date itself often changes the signal — especially when activist intent is involved.
- Learn
The Hidden Risks of Following Institutional Trades: Lag, Liquidity, and Position Sizing
A famous fund name on a 13F can be useful, but copying the trade blindly is where retail investors get into trouble. Here is how delay, liquidity, and sizing distort the signal.
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Why Loomis Sayles’ Q4 2025 13F Jumped From $84.1M to $82.47B
Loomis Sayles, long associated with fixed income and the Dan Fuss legacy, suddenly reported $82.47B in Q4 2025 13F assets after showing just $84.1M in Q3. The filing looks less like an overnight risk binge and more like a reporting-footprint reset.
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What Did Rajiv Jain Own in Q4 2025? GQG’s $60.72B 13F Put 51.3% in Its Top 10
GQG Partners reported $60.72B in Q4 2025 13F AUM across just 87 positions, with 51.3% of the portfolio concentrated in its top 10 holdings — a classic Rajiv Jain conviction profile.
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Pictet's $103.05B Q4 2025 U.S. Book Barely Budged. That's What Makes It Interesting.
Pictet Asset Management Holding SA kept its Q4 2025 13F book near record highs while refining, rather than abandoning, a quality-growth and healthcare-heavy portfolio.