| Section 16 | The part of the Securities Exchange Act that governs insider reporting (Forms 3, 4, 5). |
| Section 16(b) — short-swing rule | Forces insiders to surrender profits from any buy-and-sell (or sell-and-buy) pair within six months. |
| Insider / reporting owner | A director, officer, or >10% beneficial owner who must report their trades. |
| Beneficial ownership | Shares a person controls or profits from, whether held directly or through trusts, funds, or family. |
| Issuer | The company whose stock is being traded. |
| CIK | Central Index Key — the SEC’s unique identifier for a filer or company. |
| Accession number | The unique identifier the SEC assigns to each individual filing. |
| EDGAR | The SEC’s public system where all these filings are submitted and published. |
| Open-market transaction | A buy or sell executed on an exchange (codes P and S) — the activity with the most signal. |
| Non-derivative security | Common stock held directly (Form 4 Table I). |
| Derivative security | Options, RSUs, warrants, or convertibles (Form 4 Table II). |
| Restricted / control securities | Stock that can only be resold under Rule 144 (the realm of Form 144). |
| Acquired / disposed (A/D) | Whether a transaction increased (A) or decreased (D) the holding. |
| Rule 10b5-1 plan | A pre-arranged trading plan that lets insiders trade on a set schedule. |
| Cluster | Several distinct insiders at one company trading the same direction in a short window. |
| Net flow | Open-market buying minus selling for a company over a trailing window. |
| Amendment (/A) | A corrected re-filing (e.g., 4/A) that supersedes the original. |