What a 13F does not show

Shorts, bonds, cash, timing, non-U.S. holdings — the blind spots that make naive 13F reading dangerous.

Every quarter, headlines announce that a famous investor "bought" or "dumped" a stock, based on 13F filings. Some of those headlines are simply wrong, because the form has structural blind spots that never make it into the story.

No short positions

13Fs disclose long positions only. A fund that is long a stock's put options and short the shares can look bullish on paper while being positioned bearish overall. This is not hypothetical: long/short funds routinely hold offsetting exposures that the form cannot show. When you see a hedge fund's 13F, you are seeing at most half of a long/short book.

No bonds, cash, or most foreign listings

The form covers the SEC's official list of 13F securities: mostly U.S. exchange-listed stocks, ETFs, certain convertibles and listed options. Treasuries, corporate credit, currencies, commodities and most non-U.S.-listed shares are absent. A manager famous for a huge Japanese position may show no trace of it here.

No timing inside the quarter

A position that appears in the June 30 filing could have been bought April 1 or June 29 — possibly 20% apart in price. A position bought and fully sold within the quarter never appears at all. Quarter-end snapshots also allow window dressing: positions put on near the reporting date.

No purchase prices, no performance

Reported values are quarter-end market values. When this site estimates anything derived from prices — like separating a position's value change into share changes versus market movement — the figure is labeled an estimate, computed from the filing's own implied price (value ÷ shares), and the method is on the methodology page.

Not the whole firm

Filings aggregate accounts over which the manager has discretion, and fund families split reporting across entities. The "other managers included" fields on the cover page matter: two filings can describe overlapping assets, which is one reason we treat cross-manager totals as reported values across tracked filings, never as a measure of combined wealth.

None of this makes 13Fs useless — it makes them a specific instrument with a known field of view. The pages on this site repeat these caveats next to the numbers they affect, because the caveat is part of the number.