IPOs Explained: How Companies Go Public and What Investors Should Know

An initial public offering, or IPO, is the moment a privately held company sells shares to the public for the first time and lists them on a stock exchange such as the NYSE or Nasdaq. For the company, it raises money and creates a market price for its stock. For investors, it is a chance to own a piece of a business that was previously open only to founders, employees and private backers, with more uncertainty than most listed stocks carry.

Why companies go public

Companies list for several reasons, and the mix differs from case to case:

• Raising capital to fund growth, pay down debt or make acquisitions.
• Liquidity for founders, employees and early investors who want a way to sell shares.
• Currency for deals: listed shares can be used to pay for acquisitions or to compensate staff.
• Visibility and credibility that can come with being a public company.

Going public also has costs. Public companies must file regular reports, disclose financial results and risks, and answer to shareholders every quarter. That scrutiny, plus the expense of lawyers, auditors and bankers, is why some firms stay private for a long time.

The IPO process, step by step

1. Choosing underwriters. The company hires one or more investment banks to manage the offering. These underwriters advise on structure and price, help prepare documents, and organize demand.
2. Registration with the SEC. The company files a registration statement, commonly on Form S-1, with the Securities and Exchange Commission. It includes the business model, financial statements, risk factors, how the money will be used, and information about management and ownership. Regulators review it and may ask for changes. The SEC does not approve an offering as a good investment; it checks that required disclosure is made.
3. The prospectus. The core of the registration statement goes to investors as a prospectus. Early versions that lack a price are often called "red herrings".
4. The roadshow. Management and underwriters present the company to institutional investors and gauge demand, a process often called book-building.
5. Pricing. Based on demand and market conditions, the company and underwriters set the offer price and number of shares, usually the night before trading begins.
6. Allocation. Shares are allotted to buyers at the offer price. Institutions tend to receive most; some brokerages offer small allocations to retail customers.
7. First trade. Shares open on the exchange, and the market sets the price from that point on.

You can read the actual filings for free on the SEC's EDGAR database, and doing so is the best way to see how a company describes its own risks.

Quiet period and lock-up

Two terms come up often:

• Quiet period. Around the offering, companies and their underwriters face limits on promotional statements outside the prospectus, so that all investors rely on the same official information.
• Lock-up. Insiders and early investors typically agree not to sell shares for a set period after the IPO, commonly a few months. The exact terms are in the offering documents. When a lock-up expires, more shares can become tradable, which some investors watch as a potential source of selling pressure, though the effect varies.

Alternatives to the traditional IPO

Each route has its own rules and trade-offs, and the registration documents explain which one applies.

Reasons for caution

Newly listed companies can be exciting and can also be difficult to value. Several issues are worth understanding:

• Limited history. There may be only a few years of public financials, and a company may not yet be profitable. Compare what you read with the guidance in our explainer on reading an earnings report once quarterly results begin.
• Pricing and hype. Heavy publicity can inflate demand. A stock priced for perfection can fall even when the business performs reasonably well. Our guide to valuation ratios such as P/E and price-to-book helps put a price in context, though many young companies have no earnings to measure.
• Volatility. Prices in the early days can swing widely as supply and demand settle.
• Access gap. Because most shares at the offer price go to institutions, the price that ordinary investors pay may already include much of the early enthusiasm.
• Insider selling. Disclosures show who is selling and how much, which is useful context for how insiders see the valuation.
• Dilution and structure. Check share classes, voting rights and stock-based compensation, which can affect how much your holding is worth and what say shareholders have.

What to read before the trade

The filing itself is dense, but a few sections give most of the value:

• Risk factors, for what management says could go wrong.
• Use of proceeds, for where the money will go.
• Management's discussion of results, for how the business has actually performed.
• Financial statements, for revenue growth, margins, cash flow and debt.
• Principal and selling shareholders, for who owns what, and who is cashing out.
• Description of capital stock, for voting rights and share classes.

IPO terms you will see

A short glossary helps when reading coverage:

• Offer price: the price at which shares are sold in the offering, set before trading begins.
• Opening price: the first trade price on the exchange, which can differ greatly from the offer price.
• Underwriting spread: the fee the banks earn, usually a percentage of the money raised.
• Greenshoe (over-allotment option): an option letting underwriters sell extra shares if demand is strong, which can help steady the price in early trading.
• Float: the number of shares available to trade publicly, which can be small relative to total shares in a new listing.
• Emerging growth company: a US legal category with scaled disclosure rules, mentioned in some filings.
• Follow-on offering: a later sale of additional shares by an already public company.

Reading these terms in a filing or news article tells you who gains, who is selling and how much stock is actually available.

Frameworks, not forecasts

Whether a given IPO works out depends on the business, the price paid and the market environment, none of which can be known in advance. A sensible way to think about it is in scenarios: if growth continues and the price was fair, results can be strong; if growth slows or the valuation was stretched, shares can lag for years. Many investors prefer to wait through a few quarterly reports and the first lock-up expiry before forming a view, trading some early excitement for more information. Your own circumstances and a licensed professional are the right guides for any decision about buying.