What Is a 13F Filing?
A Form 13F is a quarterly report that certain institutional investment managers must file with the U.S. Securities and Exchange Commission (SEC). It lists most of the manager's U.S. equity holdings as of the end of that quarter.
The requirement applies to managers overseeing at least $100 million in qualifying securities. Once a manager crosses that threshold, filing becomes mandatory, not optional. The filings are published through EDGAR, the SEC's public database, which means anyone can look them up for free.
manages a portfolio above $100M
throughout the quarter
up to 45 days later
Who Files 13Fs?
The requirement covers a broad range of institutional investment managers, including:
- Hedge funds
- Asset managers and mutual fund companies
- Investment managers running discretionary accounts
- Other large institutional investors, such as pension funds and insurance companies, once they clear the threshold
Well-known names such as Berkshire Hathaway or Pershing Square file 13Fs, which is why their filings get so much media attention.
A 13F belongs to the institutional investment manager, not to a single individual. A filing from a firm associated with a famous investor reflects that firm's reported book, not necessarily that person's entire personal portfolio.
When Are 13Fs Released?
Filings are due within 45 days after each calendar quarter ends. Select a quarter below to see how the delay plays out.
By the time a 13F becomes public, the reported holdings can already be several weeks out of date. A 13F is a historical snapshot, not real-time portfolio data.
What Can You See in a 13F?
Each filing lists, for every reported security:
- Company name and ticker / security identifier
- Number of shares held
- Reported market value at quarter-end
- Portfolio weighting, which you can calculate by dividing a position's value by the total reported portfolio
- Change versus the previous filing, once you compare two quarters yourself
Simplified example portfolio
| Company | Current position | Previous position | Change |
|---|---|---|---|
| Apple | $1.2B | $900M | Increased |
| Amazon | $750M | $750M | Unchanged |
| Nvidia | $0 | $400M | Exited |
Figures are illustrative only and do not represent any real filing.
How to Read Changes Between Quarters
Comparing two consecutive filings for the same manager produces one of five outcomes:
Before versus after
A reported increase does not necessarily mean the manager is currently bullish, and it does not mean the position still exists today. It only means the share count was higher on the quarter-end date than it was on the previous quarter-end date.
What 13Fs Do NOT Tell You
This is the part beginners misunderstand most often, so it is worth being explicit.
- Company and security held
- Number of shares at quarter-end
- Reported value at quarter-end
- Change versus the prior filing
- The exact purchase price
- The exact purchase date
- Whether the position has already changed since quarter-end
- Every asset or exposure the manager holds
- Short positions, generally not inferable from the filing
- Why the manager bought or sold
- The manager's actual investment thesis
How Investors Should Actually Use 13Fs
The real value of a 13F is not copying a trade. It is a starting point for your own research process.
Repeated accumulation across several consecutive quarters is often more informative than any single quarterly change. It suggests a sustained view rather than a one-time trade.
Portfolio context matters just as much as the dollar figure. A $100 million position sounds large in isolation, but it may be a rounding error inside a $50 billion portfolio. Think in percentages and portfolio weights, not just absolute dollar values.
Practical Example
Fund XYZ reports a new $500 million position in Company ABC.
"Fund XYZ bought it, so I should buy it."
"This is a potentially interesting signal. How large is the position relative to the portfolio? Is it new? Has the fund kept accumulating? What does the company do? What is the valuation? What could the thesis be?"
A 13F change is a prompt to start research, not a conclusion to act on.
Terms Worth Knowing
Select a term to see a short explanation.
Key Takeaway
13F filings show a snapshot of reported institutional holdings at a specific point in time. They can help you discover ideas and understand portfolio changes, but they do not reveal the full investment strategy and should never replace your own research.