SEC Form 4 is the filing that corporate insiders must submit to the Securities and Exchange Commission within two business days of buying or selling company stock. While the form can look intimidating at first glance, it contains valuable information about insider sentiment—if you know how to read it.
Quick answer: Form 4 shows who traded, what they traded, when they traded, how much, and whether they bought or sold. The key sections are Table I (common stock) and Table II (options and derivatives).
Why Form 4 Matters
Section 16(a) of the Securities Exchange Act of 1934 requires corporate insiders to report their trades within 2 business days. This transparency helps prevent illegal insider trading and gives the public insight into what executives are doing with their own company's stock.
All Form 4 filings are publicly available on the SEC's EDGAR database. Invstify aggregates these filings, calculates transaction values, and flags high-conviction signals like cluster buys and C-suite trades.
Form 4 Structure Overview
A typical Form 4 is divided into:
- Header Information — who filed and for which company
- Table I — trades in common stock
- Table II — trades in options and other derivatives
- Footnotes — important context and explanations
- Signatures
Table I: Non-Derivative Securities
Table I covers trades in common stock—the regular shares you can buy on a stock exchange. This is where most meaningful insider purchases appear.
Key Columns in Table I
- Transaction Date — when the trade actually happened (not when it was filed)
- Transaction Code — a letter indicating the type of trade (see below)
- Number of Securities — how many shares were bought or sold
- Price Per Share — what the insider paid or received
- Ownership Type — D (direct) or I (indirect)
- Total Shares After Transaction — insider's total position after the trade
Transaction Codes Explained
The transaction code is one of the most important fields on a Form 4. Here's what each letter means:
- P — Purchase (bought stock on the open market) ✅ Most bullish signal
- S — Sale (sold stock on the open market)
- A — Award (stock granted as compensation)
- M — Exercise (exercised stock options)
- D — Disposition (transferred or sold shares)
- G — Gift (donated shares to family or charity)
- F — Tax withholding (shares withheld to pay taxes)
Most important: Code P (Purchase) is the most meaningful signal because it means the insider spent their own money buying stock on the open market. Code A (Award) is compensation—it doesn't represent a personal investment decision.
Ownership Type: Direct vs. Indirect
D (Direct) ownership means the insider personally owns the shares. This is the most significant type—it shows personal conviction.
I (Indirect) ownership means shares are held through a trust, spouse, LLC, or other entity. This could be for estate planning or tax reasons and is slightly less significant.
Table II: Derivative Securities
Table II covers stock options, warrants, and other derivatives. A common pattern you'll see:
- Table II, Code A — Options awarded as compensation (routine)
- Table II, Code M + Table I, Code S — Options exercised and shares immediately sold. This is usually tax-driven, not a bearish signal
Key insight: When an insider exercises options (M) and immediately sells (S), focus on whether they keep any shares. If they keep shares after the exercise, that's a positive sign.
Reading Footnotes
Footnotes provide crucial context that can change how you interpret a trade. Always check them:
- 10b5-1 plan — the sale was pre-scheduled months in advance. This is less meaningful because it was planned before any recent news
- Indirect ownership explanation — "Shares held in the Smith Family Trust"
- Vesting details — for awards, when shares vest
- Correction notice — amended filings (Form 4/A)
Red Flags vs. Green Flags
Not all insider trades carry the same weight. Here's a quick guide:
Green Flags (More Significant)
- Open market purchase (Code P) with large dollar value
- CEO or CFO buying stock
- Multiple insiders buying within the same week (cluster buy)
- Direct ownership purchase
- Insider buying when the stock is down
Red Flags (Less Significant)
- Option exercise + immediate sale (M + S) — routine compensation
- 10b5-1 plan sales — pre-scheduled, not discretionary
- Small dollar amounts (under $10,000)
- Indirect ownership transactions
- Gifts to family members
Investment Disclaimer: The information on Invstify is sourced from public SEC filings and is for educational purposes only. Nothing here constitutes financial advice. Always conduct your own research and consult a licensed financial advisor before making investment decisions.