Who has to file a 13F?

Institutional investment managers that exercise investment discretion over at least $100 million of qualifying securities must file. Individual retail investors generally do not.

Filings are due within 45 days after the quarter ends, so the information can be up to about six weeks old when it is published.

Does a 13F show what a fund sold short?

No. A 13F covers long positions in the securities it lists. Short positions and most derivatives are not shown in the same way.

How to read a 13F

A 13F is a quarterly filing in which institutional managers above a size threshold list their long positions in US-listed equities and some other securities, as of the end of the quarter. To read one, look at the issuer, the share count and value, then compare with the previous quarter to see what was added, reduced or exited. It is a snapshot from up to 45 days earlier, not a live portfolio.

What a 13F is

Institutional investment managers with at least $100 million of qualifying securities must file a Form 13F each quarter with the SEC. It lists their long positions in US exchange-traded equities and certain other securities, as of the last day of the quarter. Filings are due within 45 days of quarter end, so the 31 December positions are usually public by mid-February.

The columns that matter

Name of issuer and class. The company, and which class of its stock.
CUSIP. A security identifier, useful for matching the same security across quarters.
Value. The market value of the position at quarter end.
Shares or principal amount. The number of shares, or the principal for debt.
Investment discretion and voting authority. Who makes the decision and who votes, which matters when a filing covers several managers.

How to compare two quarters

Match the filings by CUSIP, then sort each position into one of four groups:

New. Not in the prior filing.
Added. Share count increased.
Reduced. Share count fell but the position remains.
Exited. In the prior filing, absent now.

Changes in value can also come from share price moves, so check the share count before reading a position as bought or sold.

Limits to keep in mind

It is a snapshot. Positions can change completely in the 45 days before the filing is public.
It covers longs only. Short positions and most derivatives do not appear in the same way.
It is not the whole portfolio. Cash, bonds, foreign holdings and non-13F assets are excluded.
Some positions are confidential. A manager can ask for confidential treatment on part of a holding, which removes it from the public filing for a period.

Use it as a prompt

A 13F tells you where to look, not what to do. Check the thesis, the price and the company's own disclosures before drawing a conclusion. For the broader picture, see what 13F filings show. Atradian's smart money tracker shows the latest 13F moves for tracked managers alongside insider, congressional and other filings, with the filing date printed.