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 (326)
- Learn
13F Report Date vs Filing Date: How to Avoid 45-Day Timing Mistakes
Many investors misread 13F timing. Learn the difference between report date and filing date so you stop reacting to positions that were set weeks earlier.
- Learn
How Smart Alerts Detect Unusual Institutional Activity Before Everyone Else
Learn exactly what triggers Smart Alerts on 13F Insight, how to read each signal, and a practical workflow to turn unusual institutional activity into better decisions.
- Learn
How to Export and Analyze 13F Holdings Data Outside the Platform
A practical walkthrough for using 13F Insight exports in spreadsheets and Python, with tier-specific guidance for CSV and JSON workflows.
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How to Connect AUM History With Holdings Changes to Find Real Conviction
A rising position can mean fresh buying, but it can also mean a rising stock inside a portfolio that is already getting larger for other reasons.
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How to Read a Stock Holder List Without Confusing Big Positions for Fresh Buying
A large holder is not automatically a recent buyer. Holder lists are most useful when you compare them across quarters and against portfolio context.
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How Dual-Class Share Structures Distort Insider Ownership Signals
If you only read Table I or only look at one ticker line, you can end up calling a founder out when they still control the company.
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How to Use Insider Profile Pages to Separate Routine Sellers From New Signals
The insider profile page is where you decide whether a fresh filing fits a long-running pattern or breaks from the insider's usual behavior.
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How to Read Locked Historical Quarters on 13F Insight Without Misunderstanding Tier Limits
A locked quarter does not mean the data is bad. It means the page is older than your plan allows for full detail access.
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How to Use Historical Quarter Pages Without Chasing a Stale Position
Historical quarter pages are useful when you want context, but dangerous when you forget that the portfolio snapshot is old by design.
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Why Form 4 Tax Withholding Is Not the Same as Open-Market Selling
Code F can look like insider selling in a headline, but it usually reflects shares withheld to cover taxes after vesting or exercise events.
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How to Read a Multi-Insider Cluster Without Calling It a Bearish Signal
When several executives file Form 4s around the same week, the right question is whether they sold, bought, exercised, or just covered taxes.
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How Form 4 Table I Can Mislead You About Insider Ownership in Multi-Class Companies
A Form 4 can show zero Class A shares after a sale even when the insider still controls a large beneficial stake elsewhere. Here is how to read Table I, Table II, and 13D or 13G together.
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Why Share Count Changes and Portfolio Weights Can Tell Opposite Stories in 13F Data
A manager can buy more shares and still show a lower portfolio weight, or cut shares while a position looks bigger. This guide explains how to read both signals together.
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BNP Paribas' $220.69B Q4 Jump: Mega-Cap Equity Exposure Meets Structured Overlay
BNP PARIBAS FINANCIAL MARKETS reported $220.69B in Q4 2025 and a sharp +17.8% QoQ AUM increase, combining large megacap positions with a significant non-standard top holding.
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Jennison's Q4 2025 Portfolio Is a Mega-Cap Stack: Top 10 Names Control 47.6% of $166.57B
Jennison Associates finished Q4 2025 at $166.57B, led by NVDA at $14.56B. With top-10 concentration at 47.6%, the filing shows high-conviction mega-cap growth positioning with selective breadth.
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Neuberger Berman's $134.34B Q4 Signal: Breadth Wins While Mega-Caps Lead
Neuberger Berman Group LLC reported $134.34B in Q4 2025 with only 17.5% in its top five holdings, highlighting a broad allocation model instead of concentrated single-name risk.
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CalPERS' $174.90B Q4 Blueprint: One Giant Index Core, Then AI Mega-Caps
CalPERS reported $174.90B in Q4 2025, with VOO at 11.89% and a top-10 concentration of 47.0%, combining passive core exposure with concentrated mega-cap growth.
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MFS Runs a $310.12B Book Without a 5% Position: Why Breadth Is the Signal in Q4 2025
Massachusetts Financial Services closed Q4 2025 with $310.12B and 500 positions, but no single name above 4.30%. The portfolio shows deliberate risk spreading across mega-cap compounders instead of concentrated bets.
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Northwestern Mutual’s $158.12B Q4 2025 Playbook: Why a 15.01% IVV Core Changes the Risk Math
Northwestern Mutual Wealth Management finished Q4 2025 at $158.12B, with 500 positions and a 15.01% IVV anchor that signals a rules-based, ETF-heavy allocation framework.
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Why Options-Heavy 13Fs Can Mislead Retail Investors
An options-heavy 13F can look aggressive, bearish, or brilliant when it may simply be hedged structure. Here is how to read those portfolios correctly.