How to read a Form 4 filing

A Form 4 is the document a corporate insider files with the SEC when their ownership of company stock changes. It's short — one page of structured tables — but the structure trips up first-time readers. Here's the map.

The header: who and where

The top of the form identifies the issuer (the company and its ticker) and the reporting owner (the insider), including the relationship: director, officer (with title), 10% owner, or other. One filing can have multiple reporting owners — a fund and its manager often file jointly. Each person also has a CIK, the SEC's permanent identifier, which is how we track an insider's history across companies.

Table I: non-derivative transactions

This is the table that matters. Each row shows the security, the date, a one-letter transaction code, the number of shares, the price, and whether shares were acquired (A) or disposed of (D). The last column shows shares owned after the transaction — useful for judging how big the trade is relative to the insider's existing stake.

Table II: derivative transactions

Options, warrants, RSUs, convertible notes. Most rows here are compensation mechanics. The classic trap: an option exercise shows up in Table II (code M) alongside a Table I acquisition — it looks like buying, but no market purchase happened, and it's usually followed by a same-day sale of the exercised shares.

Footnotes: where the story hides

Weighted-average price disclosures, 10b5-1 plan designations, trust and family-holding explanations all live in the footnotes. A purchase made under a pre-arranged 10b5-1 plan was scheduled months earlier and carries far less signal than a discretionary open-market buy — the footnote is the only place that distinction appears.

Or skip the parsing

We parse every Form 4 as it hits EDGAR, filter to meaningful open-market purchases, and flag when multiple insiders buy the same stock at once. Every number links back to the original filing.