What Is an SEC Form 4?

Officers, directors, and anyone who owns more than 10% of a company's stock. The law calls them Section 16 insiders. They file a Form 3 when they first become an insider, a Form 4 for each change in holdings, and a Form 5 for anything that was allowed to wait until year end.

• →The insider's name and role (CEO, director, 10% owner).
• →The date of each transaction and a one-letter transaction code. P is an open-market purchase, S is a sale, A is a grant or award, M is an option exercise, F is shares withheld for taxes.
• →The number of shares, the price, and how many shares the insider holds after the trade.
• →Since 2023, a checkbox saying whether the trade was made under a pre-arranged 10b5-1 plan.

Most Form 4s are routine: stock awards, option exercises, tax withholding, scheduled sales. The filings that carry information are open-market purchases (code P) made with the insider's own money, outside a scheduled plan. That is a small fraction of the total, and it is the fraction an insider-buying alert should be built on.

InsiderWatch reads every Form 4 as it hits EDGAR, keeps open-market buys of $50,000 or more that are not part of a 10b5-1 plan, verifies the ticker against the SEC's company list, and sends the ones that clear the bar by email and Telegram.

• →Form 3 is the initial statement. A new officer, director or 10% holder files it within ten days of becoming an insider, listing what they already own. It reports holdings, not trades.
• →Form 4 is the change report. Every purchase, sale, grant, exercise or gift that changes the insider's holdings goes on one, due within two business days of the transaction.
• →Form 5 is the annual catch-up, due within 45 days of the company's fiscal year end, for small transactions the rules let an insider defer and anything that should have been on a Form 4 but was missed.

When a headline says "insider bought", the source is nearly always a Form 4. A Form 3 showing a large holding is not a purchase, and a Form 5 is usually months old by the time it appears.

A Form 4 has two tables. Table I covers non-derivative securities, which for most readers means common stock. Table II covers derivatives: options, restricted stock units, warrants and convertible notes. Each row in Table I carries the same columns:

• →Title of security: usually "Common Stock". A different class (Class B, preferred) is worth noting because it may not be the stock that trades.
• →Transaction date: the day the trade happened, not the day it was filed. The gap between the two is the filing lag.
• →Transaction code: the one-letter code described above. This column decides whether the row means anything.
• →Amount, (A) or (D), and price: how many shares, whether they were acquired or disposed of, and the price per share. A code P row with a real market price is a purchase; a code A row at $0 is a grant.
• →Amount owned following transaction: the insider's total after the trade. Compare it with the amount traded to see whether a buy is a meaningful addition or a rounding error next to what they already hold.
• →Ownership form, D or I: direct or indirect. Indirect holdings belong to a trust, a spouse, a family partnership or a fund the insider controls, and the nature of the indirect ownership is spelled out in a footnote.

The footnotes matter more than they look. When shares were bought at several prices, the filing shows a weighted average and a footnote gives the range. A footnote may also say the trade was made under a 10b5-1 plan, or that the shares were bought in a private placement rather than on the exchange.

• →"CEO sells $10 million of stock" often describes an option exercise (code M) and the sale of the same shares (code S) on the same day. The insider converted compensation to cash; the holding may be unchanged.
• →A 10% owner is frequently a fund, not a person. A fund trimming a position on schedule says little about the company; a fund adding after a drop says a bit more.
• →A large purchase reported as indirect can be a transfer between accounts the insider already controlled. The "amount owned following" column and the footnotes show whether total ownership actually rose.
• →Shares bought in a registered direct offering or a private placement are reported with code P but were bought from the company, often at a discount, as part of a financing. Several insiders reporting the same price on the same day is the tell.
• →Late filings happen. A trade from three weeks ago that surfaces today was information three weeks ago. The transaction date, not the filing date, is the one to read.

A Form 4 documents a legal trade. Insiders may buy and sell their own stock, subject to company trading windows and to the rule that they cannot trade on material non-public information. Section 16(b) also lets the company recover any profit an officer, director or 10% holder makes from a purchase and sale of its stock within six months, which is why insiders rarely buy and then sell quickly. The filing itself is the disclosure that makes the trade lawful in the eyes of the market; the SEC pursues insiders who trade on inside information regardless of whether they filed.