What a 13F is
Investment managers with discretion over at least $100 million in certain U.S.-traded securities must file Form 13F every quarter. The form lists each position at the end of the quarter: the issuer, the class of security, its CUSIP code, the number of shares and the market value. Filings made since January 2023 report values in dollars; older ones used thousands.
Hedge funds, mutual fund companies, pension funds, banks, insurers and large family offices all file. That is how anyone can see what Berkshire Hathaway or Pershing Square held at the end of a quarter.
It is late
Managers have 45 days after the quarter ends to file. A position held on March 31 may not become public until mid-May, and the fund may have sold it by then. A 13F is a photo of the past.
It leaves things out
Short positions are not reported, so a fund that looks heavily invested in a stock may be hedged. Cash, most bonds and most non-U.S. stocks are missing too; only securities on the SEC’s official list of Section 13(f) securities count. Small positions (under 10,000 shares and under $200,000) can be left off.
A manager can also ask the SEC to keep a position confidential for a while, usually because it is still buying. Those positions often appear later in an amended filing.
It shows options in a confusing way
Listed put and call options do appear, but the value shown is based on the underlying shares, not on what the options cost. The form also gives no strike price or expiry date. A line that reads “$1 billion of puts” may represent a much smaller bet, or a hedge against shares the fund owns.
It does not say why
A 13F has no commentary. A new position can be a long-term bet, a short-term trade or one leg of a hedge. Large firms run many strategies under a single filing, so a holding may belong to one team and say nothing about the views of the firm’s best-known investor.
How WallStPal shows 13F data
For each fund we track, we compare the latest original 13F with the previous quarter and label each position as new, added, trimmed or sold out, based on the change in share count. Option positions are counted separately and left out of the holdings tables. Amended filings are not merged in yet; see our method.
Examples
Michael Burry’s “bet against the market”, August 2023. Scion Asset Management’s 13F for the second quarter of 2023 listed put options on the S&P 500 and Nasdaq 100 ETFs with a reported value of about $1.6 billion. Headlines described a $1.6 billion bet against the market. The filing could not show what the puts cost, their strike prices, when they expired, or whether they had already been sold. Because the value shown is based on the underlying shares, the money actually at risk was likely far smaller. Within months, the next filing showed the positions gone.
Berkshire Hathaway and Chubb, 2024. For several quarters Berkshire’s 13F filings hinted that something was being kept confidential. In May 2024, its filing for the first quarter revealed a stake of roughly $6.7 billion in the insurer Chubb that had been building since the previous year. Anyone reading the earlier filings could not have seen it, which is exactly how confidential treatment works.
Apple, 2016. Berkshire’s first disclosed Apple position appeared in its 13F for the first quarter of 2016, published in May 2016. By the time readers saw it, the purchases were weeks or months old. Berkshire kept adding for years, so in this case late information was still useful. With a faster-moving fund, the same delay could mean copying a trade that has already been reversed.
Explain it like I’m 13
Imagine a famous card collector who has to show the class a photo of their card binder four times a year. The rules say the photo can be taken on the last day of the term but shown up to six weeks later.
By the time you see the photo, they may have traded some cards away. The photo also only shows certain kinds of cards, and the collector does not have to explain why they own any of them. Some cards they are still collecting can even be hidden for a while.
So the photo is useful for learning what a great collector likes, but copying their binder card by card from an old photo is risky.
The takeaway for readers
Use 13F data to learn what serious investors were thinking last quarter and to build a list of ideas to research. Treat it as history, not as a live portfolio.
WallStPal explains public filings. Nothing here is investment advice. Editorial policy · Corrections