What is Form 13F

Who files it

Every institutional manager with more than US$ 100 million in US stocks and other securities on the SEC's official list: mutual funds, hedge funds, family offices, insurers, banks and foundations. Today there are close to 9,000 with a current portfolio.

Sources: Official List of Section 13(f) Securities (SEC) · Frequently Asked Questions About Form 13F (SEC, Division of Investment Management)

When it is filed

Up to 45 days after each quarter end (March 31, June 30, September 30 and December 31); if day 45 falls on a weekend, the next business day. That is why 13F “seasons” come in mid-February, May, August and November.

What it shows and what it does not

It shows long positions in US stocks (and ADRs), some options and convertible bonds, with quantity and value at quarter end. It does not show short positions, cash, non-US stocks or the purchase price. Since it arrives up to 45 days late, the portfolio may have changed.

How we use it

We read every 13F since 2013, fix scales and amendments, and compare each quarter with the previous one to see what each manager bought, added, trimmed or sold.

Which securities go into a 13F

Not everything a manager owns goes in. Each quarter the SEC publishes an official list of “13F securities”: stocks listed on US exchanges, ADRs of foreign companies, exchange-traded funds, some convertible notes, and call and put options on those securities. Cash, ordinary bonds, shares that trade only in other countries, short positions, derivatives other than listed options and private investments are left out. That is why the total of a 13F almost never matches the assets a firm manages: a fund with half its portfolio in bonds or European shares shows only the other half in its 13F. Very small positions can also be omitted: those under 10,000 shares and under $200,000.

What each line contains

Each line of the table is one security: the issuer's name, the class (common stock, ADR, option), the CUSIP, which is the code that identifies the security, the market value on the last day of the quarter, the number of shares and, for an option, whether it is a call or a put. It also says who decides on that position and how many votes the firm controls. It carries no purchase price, no purchase date and no gain or loss. The value is the quarter-end value: a stock bought at 50 that closed at 80 is listed at 80. Since 2023 values are reported in dollars; before that they were in thousands, which is why figures in older filings look a thousand times smaller.

Deadlines for each quarter

A 13F is filed within 45 calendar days after the end of each quarter. If day 45 falls on a Saturday, Sunday or federal holiday, the deadline moves to the next business day. In practice there are four dates a year: mid-February for the fourth quarter, mid-May for the first, mid-August for the second and mid-November for the third. Most large firms file in the last two or three days, so nearly all the information arrives together. One consequence follows: when you read a 13F, the snapshot is at least 45 days old, and the manager may have sold the position the day after quarter end without the filing showing it.

Amendments, notices and confidential treatment

A 13F can be corrected with an amendment (13F-HR/A). There are two kinds: one that replaces the whole filing and one that only adds positions. It matters which one it is, because treating a partial amendment as a full one doubles or erases holdings. Another variant is the 13F-NT, a notice that the positions of that entity are reported by another firm in the same group; it has no table. A manager can also ask the SEC to keep a position it is still building confidential for a while: if the SEC agrees, that line is missing from the original filing and shows up months later in an amendment. It is rare, but it explains why a large position sometimes “appears” with an old date.

Common mistakes when reading one

Four mix-ups come up again and again. One: treating the 13F as the whole portfolio, when shorts, bonds and anything listed outside the United States are missing. Two: reading a put option as a certain view that the stock will fall; it may hedge another position that is not visible. Three: attributing to a person what a firm reports; the entity files the document, with the positions of all its funds and managers. Four: comparing values across quarters without separating what changed because of price from what changed because the manager bought or sold. Looking at the number of shares, which does not depend on price, is how to tell them apart.

Who files it today

About eight thousand entities file a 13F each quarter. Most are not hedge funds: they are wealth advisers, banks, insurers, pension funds and managers of index funds. That is why “what 13F filers buy” as a whole looks a lot like the index. This site separates a smaller group, concentrated managers, defined by the shape of the portfolio (few positions, a lot of weight in the top ten and low turnover), and within it shows the type of each filer with the evidence it comes from. The well-known investors with their own page are a different group, picked by hand.