Glossary
What is a 13F filing (and how to read one)
A 13F is a quarterly report that large institutional managers file with the SEC, disclosing the US-listed stocks they hold. Any manager with at least $100 million in qualifying securities must file within 45 days of each quarter's end. The filing lists long positions only: exchange-listed stocks, some options, and convertible notes. It leaves out short positions, cash, and most non-US holdings, so it is a partial view of a fund. Because it arrives up to 45 days late, a 13F tells you what a manager owned at the close of last quarter, not what they are trading now.
By The Brief Equity Team · Published
What a 13F actually discloses
A 13F reports the long US-equity positions of an institutional manager as of the last day of a quarter. It covers Section 13(f) securities: mostly exchange-listed and Nasdaq stocks, plus some equity options, convertible notes, and ADRs. The SEC publishes it free on EDGAR within about 45 days of quarter-end.
The threshold is what makes 13F data useful. A manager only has to file once they exercise investment discretion over at least $100 million in qualifying securities, so the set of filers is essentially every large hedge fund, mutual fund, pension, and endowment in the US. That is why one filing type gives you a read on the whole institutional world.
Each filing is timestamped and permanent. Once a fund files, the report sits on EDGAR for good, which is what makes quarter-over-quarter comparison possible: you can line up the same manager across years and watch positions build and unwind.
How to read the holdings table
| Column | What it tells you |
|---|---|
| Name of issuer | The company held, one row per position |
| Value | The market value of the stake at quarter-end |
| Shares or principal amount | How many shares the manager held |
| Put/Call | Marks a position held through options rather than stock |
Read it as a snapshot, not a story. Each row is one position at one moment; the filing does not show the entry price, the conviction behind it, or when the manager bought. To read intent, you compare two filings: a brand-new position in size means more than a stake that has sat untouched for years.
One quirk worth knowing is the scale of the Value column. The reporting convention has changed over time, so a figure can be in thousands of dollars or in actual dollars depending on the vintage of the filing. Check the header before you read a number as a dollar amount, or let a tool normalize it.
What a 13F leaves out
- Short positions: 13Fs report longs only, so a fund that is net short a name still looks long on paper.
- Cash, bonds, and most non-US securities, which never appear.
- Derivatives beyond the listed options that qualify, so swaps and other exposure stay hidden.
- Timing: the filing is up to 45 days old the day it publishes, and older still by the time you read it.
These gaps are the reason a 13F is a lead, not a verdict. A manager can look heavily long a stock on a 13F while hedging it entirely with instruments that never make the filing. Treat the report as a public window into the long book, and size your conclusions to what it actually shows.
13F vs 13D vs 13G
| Filing | Who files it | What it signals |
|---|---|---|
| 13F | Managers over $100M, quarterly | The full long US portfolio, delayed |
| 13D | An investor crossing a large ownership stake | An active or activist interest in one company |
| 13G | A large but passive holder | A big stake with no intent to influence control |
The number is the form, not the concept. A 13F is a portfolio-wide snapshot filed by the manager; a 13D or 13G is triggered by a single large stake in one company and says something about intent toward that company. If you want the activist angle, the 13D is the filing to read.
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Frequently asked questions
- What is the 13F filing threshold?
- $100 million. A manager that exercises investment discretion over at least $100 million in Section 13(f) securities must file Form 13F within 45 days of each quarter's end.
- How current is 13F data?
- It is delayed. A 13F can arrive up to 45 days after the quarter it covers, and it reports positions as of quarter-end, so it shows what a manager owned then, not what they are trading now.
- Are 13F filings free?
- Yes. Every 13F is public and free to read on SEC EDGAR. Tools that join filings across quarters and compute the changes may charge, but the filings themselves cost nothing.
- Do 13Fs show short positions?
- No. A 13F lists long positions in qualifying US securities only. Short positions, cash, and most non-US holdings never appear, so a fund can look long a stock it has actually hedged.