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
Morgan Stanley's $1.68 Trillion Portfolio Has 8,095 Stocks. Here's Where the Real Bets Are.
Morgan Stanley's Q4 2025 13F reveals an ultra-diversified $1.68T portfolio across 8,095 positions — but the top-5 concentration is just 15.3%. We break down where the wealth management giant is actually placing conviction bets.
- News
Six Members of One Family Have Filed 14,000 Insider Transactions at a Forklift Company. They're Net Buyers.
The Rankin family controls 44% of Hyster-Yale and has filed more insider transactions than most Fortune 500 CEO teams combined — across three public companies they built from a coal business.
- News
Ralph Lauren Has Never Bought a Share of His Own Company. He's Sold $1.7 Billion.
The founder of the $14B fashion empire has filed 1,507 Form 4 transactions since 2004 — all sells, gifts, and tax withholdings. Zero purchases. His latest move: a $71.5M sale near the all-time high, followed by a $400M gift.
- Research
CEO Buys vs Option Exercises: How to Read Form 4 Correctly
How to separate true insider conviction from mechanical option-related flows in Form 4 filings.
- Research
Sanders Capital Exits $1.6B in China and Oil, Opens $2.3B Salesforce Bet: The Q4 2025 Value Pivot
Sanders Capital's $86.8B portfolio exits Alibaba, Halliburton, and Schlumberger while opening a $2.3B Salesforce position and doubling its Lockheed Martin stake — a decisive Q4 2025 value pivot.
- Research
Bridgewater Doubles Its Portfolio to $27.4B After a Record 33% Year - Q4 2025 13F Breakdown
Bridgewater Associates doubled its 13F portfolio to $27.4B in Q4 2025, expanding to 1,040 holdings after Ray Dalio's exit and a record 33% return in its Pure Alpha fund.
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Bridgewater Doubles Its Portfolio to $27.4B After a Record 33% Year — Q4 2025 13F Breakdown
Bridgewater Associates doubled its 13F equity portfolio to $27.4B in Q4 2025, adding 549 new holdings. After Ray Dalio's formal exit and a record 33% Pure Alpha return, we break down the fund's systematic, diversified approach.
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Armitage Sold Every Share of META and Built a $1.36B Amazon Position in Its Place: Inside Egerton’s Q4 2025 Portfolio Reconstruction
John Armitage exited 9 positions including META ($397M) and Progressive, then opened 10 new ones led by a $1.36B Amazon bet at 14.8% of portfolio. More than half of Egerton’s $9.2B portfolio is entirely new.
- Research
BlackRock Added 81 Net Holdings in Q4 2025 While Keeping a Mega-Cap Core
BlackRock, Inc. reported $5916.35B in Q4 2025 13F assets with top-10 concentration at 30.44%. We break down what changed and what retail investors can act on.
- Research
Canadian Oil at #1 in a PepsiCo-and-P&G Portfolio: Inside Yacktman's $7.1B Consumer Brand Fortress
Yacktman's Q4 2025 13F reveals Canadian Natural Resources at #1 (8.9%) in a portfolio famous for PepsiCo, P&G, and Coca-Cola. Inside the $7.1B consumer-value strategy with +146% unrealized gains on oil.
- Research
Zero Tech in the Top 5: How Dodge & Cox Built a $185B Portfolio That Ignores Silicon Valley
While most institutional giants chase the Magnificent Seven, this 95-year-old value fund puts financials, defense, and healthcare in its top 5 holdings — and its $185B AUM keeps growing.
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Carlyle’s 13F Reveals a $9B Medline Stake and a $4.4B StandardAero Hold: Inside the PE Giant’s 99%-Concentrated Two-Stock Portfolio
Carlyle Group’s Q4 2025 13F shows 99% of its $13.6B portfolio in just two recent IPOs — Medline (healthcare, $9B) and StandardAero (aerospace, $4.4B) — the clearest snapshot of PE-to-public transition in any 13F filing.
- Learn
13F Filing Season Guide: What to Watch and When
13F filing season happens four times a year, 45 days after each quarter ends. Learn the exact deadlines, what to watch for, and how to use 13F Insight to track institutional portfolio changes as they're filed.
- Learn
How to Read Whale Scores: Measuring Institutional Investor Quality
Whale Scores rank institutional investors on a 0-100 scale using three factors: AUM size, portfolio concentration, and filing activity. Learn how to interpret them and find high-conviction money managers.
- Research
SoftBank Sold $6B in NVIDIA to Fund OpenAI and Bet $3.2B on Intel: Inside Masa Son’s $15.5B Q4 2025 AI Infrastructure Pivot
Masayoshi Son exited a $6B NVIDIA position (51% of portfolio) and deployed $10B+ into Intel ($3.2B direct investment), a Bitcoin treasury company ($781M), and Taiwan Semiconductor ($603M) — all to fund a $40B OpenAI commitment. SoftBank’s Q4 2025 13F reveals the most radical portfolio rotation of the filing season.
- Research
ValueAct Deployed $3.9B in One Quarter and Doubled to 16 Holdings: Inside Morfit's $7B Activist Reload With $783M Amazon and a Live Entertainment Empire
ValueAct's 13F portfolio surged from $3.1B to $7.0B in Q4 2025 — a 125% increase in a single quarter. Mason Morfit doubled the firm's positions from 8 to 16, deploying $3.4B into new stakes including Amazon ($783M), BlackRock ($744M), Roblox ($484M), Disney ($350M), and a $564M Live Nation complex across three tickers.
- Research
Gerstner Slashed Broadcom 96% and Dumped Alibaba to Build a $6.7B AI Infrastructure Portfolio: Inside Altimeter's Q4 2025 Conviction Rotation
Brad Gerstner cut Broadcom from $246M to $11M, exited Alibaba entirely, and deployed $2.4B into 8 new positions including Microsoft, Amazon, Snowflake, and CoreWeave — reshaping Altimeter's $6.7B portfolio around an AI infrastructure super cycle thesis.
- Research
Einhorn Is Closing Greenlight to New Money After Gold Delivered 14.5% Alpha: Inside the $2.85B Q4 2025 Portfolio With a 21% Homebuilder Bet
David Einhorn announced Greenlight Capital will close to new investors on July 1, 2026, calling the US equity market 'the most expensive we've seen since we began managing money.' The fund returned 9% in 2025 (vs S&P 500 +17.9%), but macro investments — primarily gold (+64%) and copper (+40%) — contributed 14.5% alpha. The Q4 2025 13F reveals GRBK still dominates at 21%, GPK surged 79%, and Einhorn's net long exposure is just 39%.
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Point72 Bet $1.1B on a Single Biotech While Soros Built a $10.9B Healthcare Empire: How 7 Whale Funds Played the Sector in Q4 2025
Healthcare was the quiet consensus trade of Q4 2025. Point72 put $4.3B (11.3% of its portfolio) into healthcare led by a $1.1B BridgeBio bet. Soros deployed $10.9B across 37 positions. DE Shaw held 31 healthcare names worth $10.9B. But the approaches diverged wildly — from biotech moonshots to managed care defensives. A cross-fund breakdown.
- Research
The AI Chip Divide: Micron Surged 77% in Institutional Holdings While ARM Declined — Q4 2025 Semiconductor Breakdown
Institutional investors added 883 new positions in Micron and 856 in AMD during Q4 2025, but NVIDIA barely grew despite being a $3 trillion position. ARM was the only major semiconductor to lose value. Here's where 5,578 institutions stand on the AI chip trade.