What Is an IPO? Should You Invest in New Stock Offerings?

Written by Jim Norris · NorrisAI AlphaLens · Updated August 2026

Quick answer: An IPO (Initial Public Offering) is when a private company sells shares to the public for the first time, listing them on a stock exchange. IPOs can generate enormous excitement — and enormous losses. The research on IPO performance is sobering: on average, IPOs underperform the broad market significantly over the 3–5 years following listing. The few exceptional performers draw all the attention; the many poor performers are forgotten. Most retail investors are better served by waiting for post-IPO data to accumulate before evaluating a new listing.

How the IPO process works

A company decides to go public, typically to raise capital for growth, provide liquidity for early investors and employees, or establish a public currency for acquisitions. The company hires investment banks as underwriters, files an S-1 registration statement with the SEC (a goldmine of business information), and goes on a "roadshow" presenting to institutional investors.

The underwriters set the IPO price based on investor demand, and shares begin trading on the opening day. "IPO pop" — a sharp first-day price increase — is common when demand exceeds supply at the offering price. Retail investors rarely get shares at the IPO price; they typically buy in the open market after trading begins, often at a significant premium to the offering.

The IPO performance reality

Academic research consistently shows that IPOs underperform comparable public companies over 3–5 year horizons after listing. Several reasons drive this:

Timing bias: companies go public when conditions are favorable — typically near market peaks or in hot sectors where valuations are elevated. They're selling when it's a good time for them to sell, which is often not the best time for investors to buy.

Information asymmetry: company insiders know far more about the business than outside investors. When insiders choose to sell, they generally do so when they believe the price is full or higher.

Lock-up expiration: insiders are typically locked up for 180 days after the IPO. When the lock-up expires, selling pressure from employees and early investors can weigh on the stock.

Hype premium: IPOs often price in optimistic projections. When reality falls short — as it often does — multiple compression follows.

Professor Burton Malkiel of Princeton University has documented that IPOs, as a class, significantly underperform the market over the first 3–5 years after issuance. The lottery-ticket appeal of "getting in early" obscures the statistical reality that most IPOs disappoint long-term investors. — A Random Walk Down Wall Street, W.W. Norton

What to look for if you do evaluate an IPO

Read the S-1. This is the best source of unfiltered information about the business — risk factors, financial history, and management discussion of the business. It's written for legal compliance, not marketing, which makes it more candid than most investor materials.

Evaluate the business, not the story. Is there a real competitive moat? Are revenues growing sustainably? Is the path to profitability credible? What's the unit economics story?

Check who's selling. Is the IPO primarily raising new capital for the company (good) or allowing early investors and insiders to cash out (more concerning)?

Consider waiting. The post-IPO period often brings a better entry point as initial hype fades and more financial data becomes available. Many great businesses were better buys 6–12 months after their IPO than on day one.

Peter Lynch noted that some of the best investments he ever made were in companies that had been public for years — boring businesses that had been ignored while they compounded quietly. The IPO frenzy rarely produces the best long-term entry points.

How AlphaLens analyzes recent IPOs

AlphaLens works on any US-listed stock — including recent IPOs with limited public history. The Full Company Breakdown draws on the S-1 and subsequent filings; the Earnings Quality Analyzer checks early revenue recognition patterns that often signal problems in new listings; the Management Quality Scorecard evaluates capital allocation from the founding team's track record before the IPO. For newer companies with limited history, the Fair Value Stress Test's pessimistic scenario becomes especially important.

Where to go deeper

For a detailed walkthrough of each research framework, see the complete guide to all 15 AlphaLens frameworks.

For definitions of investing terms, see the AlphaLens investing glossary.