Form 4 is due in two business days. Here is what that actually means.

If you are an officer, a director, or a holder of more than 10% of a public company's registered stock, Section 16 of the Securities Exchange Act makes your trades public on a clock. Three forms carry that duty, and each has its own deadline.

Form 3: 10 days after you become an insider

The SEC's own instructions put it plainly: Form 3 must be filed within 10 days after the person becomes an insider — a new officer, a new director, or someone crossing the 10% threshold. Form 3 is a snapshot of what you hold on day one, even if that is nothing. A zero-holdings Form 3 is still required. Source: SEC, Forms 3/4/5 general instructions (sec.gov).

Form 4: two business days after the transaction

Form 4 must be filed within two business days following the transaction date. Not calendar days — business days. Buy stock on a Friday and the form is due by end of day Tuesday. The clock runs from the execution date of the trade, not the settlement date, and not the day your broker's confirmation email arrives. This is the deadline that catches people, because two business days is not much time to notice a trade, collect the details, prepare the form, and get it through EDGAR.

Form 5: 45 days after fiscal year end

Form 5 is the annual catch-up. It is generally due no later than 45 days after the company's fiscal year ends, and it reports transactions that were exempt from Form 4 reporting during the year plus anything that should have been reported earlier and was not. If everything was reported on time during the year and nothing exempt is outstanding, many insiders have no Form 5 to file at all.

The part people miss: the company is usually doing the filing

Legally the filing obligation belongs to the insider. Practically, at most small public companies, someone inside the company — the CFO, the controller, outside counsel — prepares and files these forms on the insider's behalf using EDGAR filer codes. That works until the person doing it leaves, or the trade happens on a day nobody is watching. A missed Form 4 is visible to anyone reading the filing dates, and the company must disclose delinquent Section 16 filings in its annual proxy statement under Item 405 of Regulation S-K.

What good hygiene looks like

Every insider trade should trigger a same-day note to whoever files. The two-business-day math should be computed from the execution date, with weekends and federal holidays excluded. And every filed form should tie back to a broker confirmation, not to memory.

Sources. SEC Forms 3, 4 and 5 general instructions, sec.gov. Exchange Act Section 16(a); Rule 16a-3. This article is general information, not legal advice — your securities counsel owns the judgment calls.