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 (815)
- Learn
Momentum Investing: Betting That Trends Continue
Momentum investing buys what's already winning, betting that recent trends persist, the philosophical opposite of value. Learn why this behaviorally driven pattern has been so persistent, the violent reversal risk built into it, how it complements value, and how it shows up in a 13F.
- Learn
Pharmacy Benefit Managers (PBMs): The Healthcare Middlemen
Pharmacy benefit managers sit between drugmakers, insurers, and pharmacies, deciding what your plan covers and what pharmacies get paid. Learn how PBMs make money, why their rebate and spread-pricing model draws regulatory fire, and why healthcare investors take big positions in them.
- Learn
Battleground Stocks: When Smart Money Disagrees
Some stocks become battlegrounds, names where serious investors take large, opposing bets and back conflicting views with real money. Learn what creates a battleground, how high short interest beside heavy ownership reveals one, and why a contrarian manager's outsized stake is an invitation to dig in.
- Learn
Gross vs Net Exposure: How Much Is a Fund Really Betting?
A hedge fund's assets tell you little about its real market risk, that lives in gross and net exposure. Learn how gross (longs plus shorts) measures total risk and leverage, how net (longs minus shorts) shows directional lean, and why a 13F, showing only longs, can badly mislead.
- Learn
Uranium and Nuclear Energy Investing Explained
After a decade in the wilderness, nuclear power is back as an investment theme, driven by AI data-center demand, clean-energy needs, and energy security. Learn the chain from uranium miners to reactor builders and SMRs, the supply-demand case behind it, and the commodity and political risks.
- Learn
Conviction Buys vs Forced Selling: Reading Intent in a 13F
A fund's shrinking assets and trimmed positions look bearish, but often aren't, the manager may just be raising cash for redemptions. Learn to tell forced, flow-driven selling from genuine conviction in a 13F, why buying against a falling asset base is the clearest signal of all.
- Learn
How Interest Rates Affect Stock Prices
Buffett likened interest rates to gravity for asset prices. Learn the channels through which rates move stocks, discounting future cash, competition from bond yields, debt costs, and the economy, why growth and income stocks are most sensitive, and how a 13F reveals rate exposure.
- Learn
Bid-Ask Spreads and Liquidity: The Hidden Cost of Trading
Every trade has two prices, the bid and the ask, and the gap between them is a real, often invisible cost. Learn how the bid-ask spread measures liquidity, why it widens in small caps, why scale and small-cap investing are in tension, and what a 13F reveals about a manager's liquidity risk.
- Learn
Equal-Weight vs Cap-Weight: How Much of Each Stock?
How much of each stock you own can matter as much as which stocks you pick. Learn how cap-weighting concentrates a portfolio in the largest companies, how equal-weighting tilts toward smaller and cheaper names with built-in rebalancing, and how a 13F reveals which a manager uses.
- Learn
Toll-Booth Businesses: Getting Paid for the Flow
A toll road earns the same fee whether the cargo is cheap or expensive, it just needs traffic. Learn why fee-based, toll-booth business models, pipelines, payment networks, exchanges, produce such steady cash flows, what still threatens them, and why they anchor income portfolios.
- Learn
MLPs and K-1 Forms: The Structure Behind Pipeline Yields
Many big energy-infrastructure names are master limited partnerships, not ordinary corporations, which avoids double taxation but issues a Schedule K-1 instead of a 1099. Learn how the MLP structure works, the tax and paperwork trade-offs behind those high pipeline yields, and how MLPs appear in a 13F.
- Learn
Market-Cap Tiers: Why a Company's Size Matters
A company's market cap shapes how its stock behaves, who owns it, and what edge is even possible. Learn the size tiers from mega- to micro-cap, the small-cap risk-and-opportunity trade-off, why scale pushes big funds toward megacaps, and how a 13F reveals the game a manager plays.
- Learn
Correlation: Why Diversification Is About Difference, Not Count
Owning fifty stocks isn't diversified if they all move together. Learn how correlation, not the number of holdings, drives real diversification, why it is called the only free lunch in investing, why correlations spike toward 1 in a crisis, and how to read it in a 13F.
- Learn
Reinvestment and Return on Incremental Capital
Two companies with the same profits can have wildly different futures, depending on what they can do with each new dollar. Learn return on incremental capital and the reinvestment runway, the engine behind true compounders, and why a cash cow is a different kind of investment.
- Learn
The Sharpe Ratio: Measuring Return Against Risk
A 20% return isn't automatically better than 12%, it depends on the risk taken. Learn how the Sharpe ratio measures excess return per unit of volatility, why a steadier portfolio can be the more skillful one, what the ratio misses, and why risk-adjusted thinking matters.
- Learn
Holding Cash: Why Dry Powder Is an Active Decision
For disciplined value investors, holding cash is an active choice, not leftover money. Learn why managers keep dry powder when stocks look expensive, how it cushions drawdowns and funds bargains in a panic, the real cost of cash drag, and why a 13F can't show it.
- Learn
Emerging Markets Investing: Higher Growth, Different Risks
Emerging markets offer some of investing's most compelling growth stories alongside its sharpest risks, volatile currencies, abrupt policy shifts, thinner liquidity. Learn what makes EM different, why investors are drawn to it, and how to read emerging-markets exposure in a 13F.
- Learn
Network Effects: The Moat That Widens With Scale
A network effect makes a product more valuable as more people use it, the rare moat that strengthens with scale instead of eroding. Learn how it powers payment networks, marketplaces and platforms, why two-sided networks are hardest to dislodge, and how it shapes quality portfolios.
- Learn
Operating Leverage: Why Profits Swing More Than Sales
Operating leverage explains why a company's profits can jump 30% on 10% more revenue, or collapse far faster in a downturn. Learn how fixed costs act as a profit multiplier in both directions, why software soars and airlines suffer, and how it shapes the risk in a 13F's holdings.
- Learn
The Math of Drawdowns: Why Avoiding Losses Matters Most
A 50% loss needs a 100% gain just to break even, and the math only gets crueler from there. Learn why this asymmetry makes capital preservation central to compounding, how avoiding deep drawdowns protects the long-term runway, and how the discipline shows up in a 13F.