Insider Trading Basics
Educational Content: This page explains SEC reporting rules and public filing data. It is not investment advice and not a recommendation to buy or sell securities. All trading involves risk.
What is insider trading?
The term covers two different things. Illegal insider trading is a trade made on material non-public information in breach of a duty of trust. Legal insider trading is a routine trade by a company officer, director, or large shareholder, reported to the SEC on a public form. The second kind is what filing data shows. A filing on its own never tells you that a trade was illegal.
Who counts as an insider?
Section 16 of the Securities Exchange Act of 1934 defines the reporting group. Three categories must report their trades in the company's stock.
| Category | Definition |
|---|---|
| Officers | Executives with policy-making authority, such as the CEO, CFO, and COO |
| Directors | Members of the board of directors |
| 10% owners | Holders of more than 10% of a registered class of the company's equity |
A person can be in more than one category. A founder who sits on the board and holds 15% of the stock is both a director and a 10% owner.
What do insiders file, and when?
| Form | Purpose | Deadline |
|---|---|---|
| Form 3 | First report of the person's holdings | Within 10 days after the person becomes an insider |
| Form 4 | Report of a change in holdings | Before the end of the second business day after the transaction |
| Form 5 | Annual report of small or exempt transactions | Within 45 days after the fiscal year ends |
Form 4 is the common one. It carries the date, the share count, the price, the transaction code, and the person's holdings after the trade. See Form 4 Explained for a field-by-field walkthrough.
You can read the full Form 4 history for any company on its filing page. For example, /form4/aapl/ lists every reported Apple insider transaction, and /insider/ is the directory of individual insider profiles across companies.
Transaction codes
The code tells you what kind of transaction happened. Two trades of the same size can mean very different things.
| Code | Meaning |
|---|---|
| P | Purchase, on the open market or in a private deal |
| S | Sale, on the open market or in a private deal |
| A | Grant or award from the company |
| M | Exercise of a derivative, such as a stock option |
| F | Shares given back to the company to pay tax |
| G | Gift |
A code A grant is compensation. The insider did not choose to buy. A code P purchase means the insider paid cash. A code F transaction is usually automatic and follows a vesting date. Insider Transaction Types covers each code in detail.
What is a Rule 10b5-1 plan?
Rule 10b5-1 lets an insider adopt a written trading plan in advance. The plan sets the amounts, prices, and dates, or gives a formula for them. The insider must adopt the plan at a time when the person does not hold material non-public information. A trade that follows a valid plan gives the insider an affirmative defense against a claim of illegal insider trading.
The SEC amended the rule in 2022. The current rule adds a cooling-off period between the date of the plan and the first trade under it. Since 2023, Form 4 includes a checkbox that shows a transaction followed a Rule 10b5-1 plan.
Blackout periods
A blackout period is a company policy, not an SEC rule. Most public companies close their trading window for insiders in the weeks before an earnings release. The rules differ from company to company, and the company does not publish them in the filing.
What filing data can and cannot tell you
Insider filings are a record of what happened. They are not a forecast.
Filings show:
- The date, size, price, and type of each reported transaction
- The person's role and their holdings after the trade
- Whether several insiders at the same company traded in the same period
- Footnotes that explain trusts, gifts, and plan trades
Filings do not show:
- The reason for the trade
- Whether the trade was legal or illegal
- What the stock will do next
A sale can come from a tax bill, a house purchase, a divorce, or a scheduled plan. The form does not record the motive. Treat a filing as one fact among many, alongside the company's 8-K history and its financial statements.
Context that changes how a filing reads
These questions do not produce a verdict. They stop you from reading a routine event as a rare one.
- What is the transaction code? A purchase and a grant both add shares. Only one of them cost the insider money.
- How large is the trade against the person's own position? A sale of 2% of a holding is a different fact from a sale of 60%.
- How large is the trade against the company? A 2 billion company is small.
- Did the footnote name a Rule 10b5-1 plan? A plan trade was set months in advance.
- How does this compare to the person's past filings? A first purchase in three years is a different fact from a monthly pattern.
- Did other insiders file in the same window? Several filings in a short period are less easy to explain as one person's cash need.
Common mistakes
Treating every sale as bad news. Insiders sell for reasons that have nothing to do with the company. Check the code, the size against holdings, and the footnotes first.
Ignoring the dollar amount. Five insiders who each bought 2 billion company have moved $25,000. Count the money, not the filings.
Reading grants as purchases. Code A and code M transactions come from a pay package. Code P is the one where the insider spent cash.
Treating a filing as a conclusion. A Form 4 is a data point. It reports the past. It does not tell you what happens next, and it never tells you a trade was improper.
Common questions
How fast does a trade become public? An insider must file Form 4 before the end of the second business day after the transaction. Profitelligence reads the filing within minutes of its arrival at the SEC.
Can insiders trade during a blackout period? Company policy normally forbids it. Rule 10b5-1 plans are the usual exception, because the insider set the trade up in advance.
How do I know if a sale followed a 10b5-1 plan? Look for the Form 4 checkbox, and read the footnotes. Regular sales of a similar size on a regular date often come from a plan.
Can I tell from a filing that someone broke the law? No. A filing shows a transaction. Proof of illegal insider trading needs evidence about what the person knew and when. Only the SEC and the courts make that finding.
Next steps
Read Form 4 Explained for the layout of the filing itself. Read Insider Transaction Types for the full code list. To see the data, open the Insider Trading Dashboard or a full company page such as profitelligence.com/company/AAPL.