Key points
- A 13F is a quarterly filing that lists the US stock holdings of big investment managers, those running $100 million or more. It is public and free to read.
- It comes with a catch: managers have up to 45 days after a quarter ends to file, so a 13F shows the past, not a live feed.
- It shows long US-listed stocks and options, but not short positions, cash, bonds, or foreign-listed shares, so it is only part of the picture.
- For big concentrated bets, 13D and 13G filings (for stakes above 5%) show up within days, much faster than a 13F.
There is something genuinely fun about getting to see what the big money is buying. Every quarter, the largest investment managers have to hand the SEC a list of their US stock holdings, and anyone can read it for free. That filing is called a 13F, and it is the paper trail behind headlines like Leopold Aschenbrenner's fund building a stake in SharonAI. Here is what a 13F is, what it does and does not tell you, and how to track them yourself.
What a 13F filing is
A 13F, formally Form 13F, is a report that an institutional investment manager must file with the SEC if it controls at least $100 million in US-listed securities. Hedge funds, mutual funds, pensions, and large family offices all cross that line. They file once per quarter, and the filing lists each US stock position by company name, a securities identifier called a CUSIP, the number of shares, and the dollar value. So when people say a fund "disclosed a new position," they usually mean it showed up on the latest 13F.
The 45-day catch
This is the most important thing to know before you read too much into any single filing. A manager has up to 45 days after a quarter ends to file its 13F. So a filing that lands in mid-May is describing what the fund held back on March 31. By the time you read it, the manager may have already added to the position, sold it, or changed its mind entirely. A 13F is a snapshot of the past, not a live view of what someone is doing right now.
What it shows, and what it hides
A 13F is also a one-sided picture, and knowing what is missing is the difference between using it well and being fooled by it.
It includes long positions in US-listed stocks and ETFs, plus put and call options on those names. It does not include short positions at all, so you cannot see what a manager is betting against. And it leaves out cash, bonds, and anything that trades only on a foreign exchange. So a fund that looks all-in on a handful of stocks in its 13F might actually be heavily hedged, or sitting on a pile of cash, in ways the filing will never show you.
13F versus 13D and 13G: catching the big bets faster
If a 13F is the slow quarterly snapshot, 13D and 13G filings are the fast ones. When an investor crosses 5 percent ownership of a single company, it has to file one of these, and the deadlines are days, not months. A 13D signals an active or control intent and is due within a few business days; a 13G is the quieter, passive version. This is how you catch a big, concentrated bet almost as it happens. When Situational Awareness took its SharonAI stake to 19.9 percent, that showed up in a 13G, not a quarterly 13F. And a company's own officers and directors file even faster, in Form 4 filings, the way the S&P Global CEO's purchase did.
How to track them yourself, for free
All of this is public on the SEC's EDGAR database. You can search a manager by name, open its latest 13F, and read the holdings list line by line. The trick to staying current without paying for anything is to know the calendar: 13Fs cluster right around the 45-day deadline after each quarter, so mid-February, mid-May, mid-August, and mid-November are the busy windows. For 5 percent stakes, watch for 13D and 13G filings, which can land any time someone crosses the line.
How we track them here
Reading EDGAR by hand works, but it is slow, which is why we built a fund tracker into the site. It watches the filings of a set of well-known managers and surfaces the new ones quickly, so you can see what changed without refreshing EDGAR all day. You can open a single manager, like Situational Awareness, and read the holdings behind the headlines, whether that is a green bitcoin miner or Michael Burry's options bets. One thing to keep straight: congressional trades, like Nancy Pelosi's and Dave McCormick's, are a different kind of filing under a different law, which we track over on the Congress page.
What a 13F is actually good for
So how should you use one? A 13F is a great way to spot themes and to see which managers are crowding into the same names, which is often more telling than any single buy. It is a weaker tool for copying trades, because the data is stale, you cannot see the shorts or the hedges, and you do not know the manager's conviction or what they paid. The healthiest way to read one is as a clue about where smart money is looking, not a signal to act on. None of this is investment advice; it is simply how to read public filings with your eyes open.
