Form 3, 4 and 5: what's the difference?
If you become a director, an officer or a 10% owner of a US-listed company, you file three kinds of forms with the SEC. Form 3 states what you own, Form 4 reports each change, and Form 5 catches what the other two left out.
Who files
Section 16(a) of the Securities Exchange Act of 1934 covers the directors and officers of a company with a registered class of shares, and anyone who owns more than 10% of such a class. They file on the SEC's EDGAR system, and each filing becomes public there.
Form 3: the starting position
You file a Form 3 within 10 days of becoming an insider. It lists the company's shares and derivatives you own on that date, directly or indirectly. You file it even when you own nothing. When a company first registers its shares, as in an IPO, its insiders file a Form 3 by the date that registration takes effect.
Form 4: each change
You file a Form 4 before the end of the second business day after a trade that changes what you own: a purchase, a sale, an option exercised, a grant. Since 27 February 2023 a bona fide gift of shares goes on a Form 4 as well. The Form 4 guide explains the two tables and the transaction codes.
Form 5: the annual sweep
A Form 5 is due within 45 days after the end of the company's fiscal year. It reports what did not need a Form 4 at the time, and what should have been on one but was not:
- Small acquisitions worth up to $10,000 in total over six months (Rule 16a-6).
- Certain transactions that are exempt from the short-swing profit rule of Section 16(b).
- Holdings and trades that you should have reported on a Form 3 or Form 4 during the year. The form marks them with a 3 or a 4 next to the transaction code, so a late purchase shows as P4.
If you have nothing of this kind to report, you file no Form 5.
The three side by side
- Form 3: within 10 days of becoming an insider; your holdings on that date.
- Form 4: within 2 business days of a trade; that trade and your holdings after it.
- Form 5: within 45 days after the fiscal year; small, exempt and unreported transactions.
Forms 4 and 5 both carry a checkbox for trades made under a 10b5-1 plan. In the EU, managers of listed companies report under MAR Article 19 instead, with one form and a three-day deadline.
Section 16 filings on this site
Insider Trades shows Form 4 filings next to the European registers, with a link to the filing at the SEC on every row. Each US company has its own page with its Form 4 history. How we read and filter the filings is on the methodology page.
Checked against the regulation and the regulator’s own pages on Oct 31, 2026. This guide explains the rules; it is not legal or investment advice.
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