IPO Center › IPO Basics and Definitions
United States · Foundations
IPO Basics and Definitions
The core terms, documents, and participant roles used across U.S. IPO markets.
A section of the IPO Center. The facts on this page follow the official text of the authorities cited below, each linked for verification.
Key facts
What the official sources actually say
Every statement below maps to a primary source listed at the bottom of this page.
An IPO is a registered public offering
In the United States, an initial public offering is conducted under the Securities Act of 1933, which requires that investors receive significant information about securities offered for public sale.
The registration statement and prospectus
Form S-1 is the registration statement used where no other form is authorized; Part I of the form is the prospectus that investors receive.
Underwriters
Underwriters are FINRA member firms that distribute the offering; their terms, arrangements, and compensation are governed by FINRA Rule 5110.
The reporting company
After the offering, the issuer becomes a reporting company, filing Forms 10-K (annual), 10-Q (quarterly), and 8-K (current reports) under the Exchange Act.
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