A simple list for the retail investor
Understanding SEC codes
Companies file by code, not by name. Nothing about the codes tells you what is inside them — a 10-Q is quarterly, an 8-K is whatever just happened, and there is no way to guess that. Sixty-five of them below, one line each. All free at sec.gov/edgar/search.
Shaded rows are the ones that matter most here.
| 10-K | Annual report | The whole year. Audited numbers, the business, the risks. |
| 10-Q | Quarterly report | Three months, unaudited. Share count on the cover, warrants in the notes. |
| 8-K | Current report | Something big happened. Four business days to say so. |
| 8-K/A | Amended current report | A fix or an addition to an 8-K already filed. |
| 10-K/A · 10-Q/A | Amended report | A fix to a report already filed. |
| NT 10-K · NT 10-Q | Late filing notice | We cannot file on time, and here is why. |
| 11-K | Employee plan report | The annual accounts of a company 401(k) or stock purchase plan. |
| ARS | Annual report to shareholders | The mailed version, with pictures. |
| 20-F | Annual report, foreign | The 10-K, for a foreign company. |
| 6-K | Current report, foreign | The 8-K, for a foreign company. |
| 40-F | Annual report, Canadian | The annual report, for a Canadian company. |
| NT 20-F | Late filing notice, foreign | A foreign company saying it will be late. |
| S-1 | Registration statement | Asking permission to sell new shares. |
| S-1/A · S-3/A | Amended registration | The same request, revised after the SEC asked questions. |
| S-3 | Shelf registration | Permission granted in advance, to sell later without asking again. |
| EFFECT | Notice of effectiveness | The SEC saying yes. Selling can start. |
| RW | Registration withdrawal | Never mind. Pulling the request. |
| 424B1 · 424B2 | Prospectus | The offering document, filed once the deal is done. |
| 424B3 | Resale prospectus | Lets someone resell shares they bought privately. |
| 424B4 | Final prospectus | The final terms after an offering prices. |
| 424B5 | Prospectus supplement | The actual deal. Price, shares, warrant terms, who got paid what. |
| FWP | Free writing prospectus | Marketing material sent to investors during an offering. |
| POS AM | Post-effective amendment | An update to permission already granted. |
| S-8 | Employee plan shares | Shares set aside for employees. No SEC review. |
| S-4 | Merger registration | Shares used to pay for a merger. |
| D | Exempt offering notice | We sold shares privately. Here is how much. |
| 1-A · 1-K | Regulation A offering | A smaller public raise, with lighter rules. |
| C · C-AR | Crowdfunding | A very small raise through a funding portal. |
| F-1 · F-3 · F-4 | Foreign equivalents | The same three forms, for foreign companies. |
| 144 | Notice of proposed sale | An insider is about to sell restricted stock. |
| 8-A12B | Exchange registration | Listing a class of shares on an exchange. |
| CERT | Exchange certification | The exchange confirming the listing. |
| SC 13D | Beneficial ownership, active | I own more than 5 percent and I may want a say. |
| SC 13G | Beneficial ownership, passive | I own more than 5 percent and I am just holding. |
| SC 13D/A · SC 13G/A | Amended ownership report | My position or my intentions changed. |
| 3 | Initial insider report | I just became an insider. Here is what I hold. |
| 4 | Insider transaction | An insider bought, sold, or was granted something. Two days to report. |
| 5 | Annual insider statement | The year-end cleanup of anything an insider missed. |
| 3/A · 4/A · 5/A | Amended insider report | A correction to an insider filing. |
| 13F | Institutional holdings | A big manager listing what it owned at quarter end. |
| 13H | Large trader registration | A registration for anyone who trades a lot. |
| SC TO-I · SC TO-T | Tender offer | An offer to buy your shares. |
| SC 14D9 | Response to a tender offer | The board telling you whether to take it. |
| SC 13E3 | Going private | Insiders buying out the public and taking the company off the market. |
| DEF 14A | Definitive proxy | What you are being asked to vote on, and why. |
| PRE 14A | Preliminary proxy | The draft of that, before the SEC sees it. |
| PRER14A | Revised preliminary proxy | The draft again, after the SEC commented. |
| DEFA14A | Additional proxy material | Extra material sent after the proxy went out. |
| DEFR14A | Revised definitive proxy | A corrected proxy. |
| DEFM14A · PREM14A | Merger proxy | A proxy about a merger. Contains the fairness opinion. |
| DEFC14A | Contested proxy | Someone is running against the board. |
| DEF 14C | Information statement | A vote already happened without you. This is the notice. |
| N-PX | How a fund voted | A fund reporting the proxy votes it cast. |
| CORRESP | Letter to the SEC | A company answering SEC questions. Signed by its lawyer. |
| UPLOAD | Letter from the SEC | The SEC asking those questions. |
| CT ORDER | Confidential treatment | Permission to keep part of a contract out of the public file. |
| 25 · 25-NSE | Delisting | Taking a stock off the exchange. |
| 15-12B · 15-12G | Deregistration | We are done filing reports. |
| SD | Conflict minerals | Where certain metals in the products came from. |
| X-17A-5 | Broker-dealer report | A broker-dealer showing its own books. |
| T-3 · 305B2 | Debt indenture | Paperwork for a bond issue and its trustee. |
| MA | Municipal advisor | Registration for advisers to state and local governments. |
| 10-D · ABS-EE | Asset-backed reports | Monthly reporting on pools of loans. |
| 497 · N-2 | Fund prospectus | The offering document for a mutual fund or closed-end fund. |
| N-PORT · N-CSR | Fund reports | What a mutual fund or ETF owns, and its annual accounts. |
One that is not on EDGAR. Form ADV is what an investment adviser files about itself — who owns it, how much it manages, and any disciplinary history. It lives at adviserinfo.sec.gov, not EDGAR. Worth knowing when a fund appears in a filing and you want to know who is behind it.
Where to start
If you only read three
Three forms carry nearly everything about a company's capital structure.
10-Q — what exists now
Share count on the cover. Warrants and options in the notes. Cash and any going-concern language in the liquidity section. Filed four times a year.
424B5 — what was sold, and on what terms
Price, share count, warrant exercise price and term, who placed it, and what they were paid. Read them in order and you can watch the terms get worse.
DEF 14A — what you are being asked to approve
The proposals, the board's reasons, insider ownership, and the quorum rule. If a company wants more authorized shares, it has to tell you what that does to yours.
Finding them
- Go to sec.gov/edgar/search.
- Type a company name or ticker.
- Or search a phrase in quotes —
"warrant inducement"— to find every company that used those words. - Filing category on the left narrows to one form type. Filed date range narrows to a period.
- Search covers 2001 onward. For older filings, browse the company's own history instead.