Definition

The SEC filing identifier assigned by EDGAR at the moment a filing is accepted. It is the durable external identity for a filing — used in the SEC URL, in our API, and in cross-system references. Format is a hyphenated sequence like 0001214128-26-000123.

SEC accession number explained

Keyword focus: sec accession number

A SEC accession number is the unique EDGAR identifier assigned to a filing when it is accepted. It is one of the safest ways to reference a filing because company names, tickers, and people can change over time.

Accession numbers appear in SEC URLs and filing index pages. In The Insiders Post, they are used as durable filing identifiers for linking normalized rows back to the original SEC source.

  • Use accession numbers to verify a filing against EDGAR.
  • They are more stable than company names or page titles.
  • A single accession number can contain multiple transaction rows.
  • They help connect parsed XML, filing detail pages, and product records.

How to read this term

Practical filing context for this specific glossary entry

Start with the filing type

The form number determines whether you are reading an initial holding, a change in ownership, an annual catch-up, or a proposed sale notice.

Use identifiers carefully

CIKs, accession numbers, and SEC URLs are durable references. They are safer than company names when matching across systems.

Do not mix surfaces

A Form 144 proposed sale is not the same thing as an executed Form 4 sale. Keep proposed-sale context separate from transaction rows.

Quick facts

Code
Priority
High signal
Scope
Every filing has exactly one accession number
Slug
accession-number