How BrainyBee reads 13F filings

Reported, not current: the 45-day lag

A 13F lists holdings as of the last day of a quarter and is due 45 days later; when that day falls on a weekend it moves to the Monday. Most managers file close to the deadline, so a filing can be six weeks or more out of date when it appears, and the manager may have traded since. Each manager page shows when its filing was made and how old it is.

A manager that misses a deadline by more than ten days is marked as having stopped filing, and its page says which quarter it last reported.

How filings are read

• Each quarter is read from the manager’s original 13F together with any amendment that restates or adds to it, so a corrected filing replaces the figures it corrects. Amendments filed long after the quarter are marked as late disclosures.
• Values are as filed: the market value the manager reported at quarter end. A position’s weight is its share of the manager’s reported 13F portfolio, which is not the manager’s total assets.
• The quarter-end value per share is the reported value divided by the reported shares. It is not a purchase price or a cost.

What changed, and what only looks like it changed

• New, increased, reduced, exited compare a quarter’s filing with the manager’s previous one. An increase is a larger reported position, not a confirmed purchase.
• Stock splits. A split changes the share count without any trade. When a split took effect between two quarters, the previous share count is adjusted by its ratio before positions are compared, and the page says so.
• CUSIP changes. When a company’s security identifier changes (after a merger, a reorganisation or a share-class change), a holding can look like an exit and a new position at once. Where the two halves can be matched they are shown as one identifier change, not as a sale and a purchase.
• Spin-offs. Shares a manager received when a company it held spun off a business are shown as received, not as a new purchase.
• Biggest moves are ranked by how much of the manager’s portfolio moved, and only once a move clears a size floor, so a small trim in a large holding is not listed as a major change.

Options and other instruments

Puts and calls are listed apart from shares. The value shown for an option is the value of the underlying shares the manager reported, not what the option is worth, and options are not counted as owning the stock. Bonds and other holdings reported by principal amount are shown as reported.

What a 13F leaves out

Short positions, cash, most non-US holdings and private investments are not reported. A 13F is a partial, delayed snapshot — useful context for research, never a trade signal.

• Confidential treatment. The SEC can let a manager keep a position out of its filing for a while, usually while it is still building or selling it. The position appears later in an amendment, which is why a late amendment can add holdings to a quarter that was already filed.
• Co-filed entities. A filing can cover several related firms or funds, and a firm’s holdings can be reported in another manager’s filing instead of its own. A 13F shows what the filing covers, which is not always one person’s or one fund’s whole portfolio.

Learn to read a 13F

Signed-in members can take a short course on how to read a 13F, with a quiz after each module, and read a style lesson for each headline manager on what its filings can and cannot show.