Guides to the Filings
Short explainers for the documents behind every number on this site. Each one has real examples and a version a 13-year-old could follow.
Insider trading
What insiders buy and sell, and how to read it.
How to Read a Form 4
A Form 4 shows when a company insider bought or sold stock, how much, at what price, and how many shares they hold afterwards. Here is how to read one, box by box.
4 min readWhat Is a 10b5-1 Trading Plan?
Many insider sales are scheduled months in advance under a Rule 10b5-1 plan. Here is how these plans work, what the 2023 rule changes require, and how to read a plan sale.
3 min readIs Insider Buying a Good Signal?
Studies going back decades find that open-market purchases by insiders have, on average, been followed by better-than-market returns. Here is what the research found, where it falls short, and how to use it.
3 min readWhat Is a Cluster Buy?
A cluster buy is when several insiders at the same company buy shares around the same time. Here is why investors watch for them and how WallStPal finds them.
2 min read
Funds and 13F
What the big funds own and what their filings leave out.
What a 13F Can't Tell You
A 13F lists a fund's U.S. stock holdings at the end of each quarter. It is useful, but it is late, partial and silent about why. Here is what to keep in mind before copying anyone.
3 min readHow to Follow Berkshire Hathaway's Portfolio
Berkshire Hathaway lists its U.S. stock holdings in a 13F filing each quarter. Here is when it comes out, how to read it, and why copying it trade for trade is harder than it looks.
2 min read
Reading SEC filings
Form 4, 13F, 10-K and the rest, box by box.