Initial Public Offering (IPO)

The first time a private company offers shares to the general public on a stock exchange — transforming private equity held by employees and investors into publicly traded, liquid stock.

An initial public offering (IPO) is the process by which a privately held company first offers shares of its stock to public investors on a regulated stock exchange. Before an IPO, a company's stock is held only by founders, employees, and private investors (angels, venture capitalists, private equity firms) and has no public market — it can only be sold through private transactions, which are typically restricted and difficult to arrange. After a successful IPO, shares are listed on an exchange such as the NYSE or NASDAQ, where any investor can buy and sell them at a market-determined price. For employees who hold equity in the company, an IPO is often the first real opportunity to convert their stock or options into cash.

The IPO process is complex and heavily regulated. Companies that want to go public engage investment banks (underwriters) who help price the offering, market shares to institutional investors through a 'roadshow,' and manage the mechanics of the listing. The company files an S-1 registration statement with the Securities and Exchange Commission (SEC), which discloses extensive financial and business information to the public for the first time. The S-1 is the primary document investors use to evaluate the company — reading it gives employees and prospective investors detailed insight into the company's revenue, growth, risks, and competitive landscape. The IPO typically prices shares in the evening before the first trading day, and the next morning trading opens, often with significant price movement in either direction.

For employees, the IPO triggers a lock-up period — typically 180 days — during which they are prohibited from selling their shares regardless of market price. This restriction exists to prevent a flood of insider selling from depressing the stock price immediately after listing. The first day an employee can sell is called lock-up expiration, and it's a critical date on every employee's calendar. In the weeks leading up to lock-up expiration, companies often see stock price pressure as the market anticipates the incoming supply from insider selling. After lock-up expires, employees are generally subject to insider trading policies that restrict selling to specific open trading windows and require pre-clearance for certain holders.

The IPO price — the price at which shares are first sold to public investors — becomes the benchmark against which the company's public market performance is measured. If the stock opens significantly higher than the IPO price, the company is said to have 'left money on the table' (they could have raised more by pricing higher). If it opens lower, early public investors are underwater. For employees, what matters is where the stock price is relative to their option strike price or RSU vesting price — and where it goes after lock-up expiration when they can actually sell. Many employees have experienced the frustration of watching the stock rise through lock-up, only to see it fall significantly by the time they can trade.

Key IPO Milestones for Employees

  • S-1 filing: the company's detailed financial disclosure to the SEC — read it carefully. It's the most honest public document the company will ever produce about its risks and business model.
  • IPO pricing: the night before listing, underwriters set the IPO price with institutional investors. This is the reference point for calculating 'first-day pop' or decline.
  • First trading day: shares begin trading on the public exchange. The opening price is set by market demand, not the IPO price — it can be significantly higher or lower.
  • Lock-up expiration: typically 180 days after the IPO, employees and early investors can sell for the first time. This date is published in the S-1 and in financial calendars.
  • Open trading windows: after lock-up, employees subject to insider trading policies can only sell during quarterly windows — typically a few weeks after each earnings report.
  • 10b5-1 plans: some employees set up pre-planned trading programs before lock-up expires that allow scheduled sales during otherwise restricted periods.

IPO vs. Direct Listing vs. SPAC

  • IPO: company raises new capital by selling new shares to public investors; underwriters guarantee a price; existing shareholders face a lock-up period. Traditional path for most companies.
  • Direct listing (DPO): company lists existing shares on an exchange without raising new capital and without underwriters. No lock-up period required for existing shareholders. Used by Spotify, Coinbase, Palantir.
  • SPAC: company merges with a pre-existing blank-check shell company that is already publicly traded — going public without a traditional IPO roadshow. Faster but often produces different valuation dynamics.
  • Each path has different implications for employees — particularly around lock-up periods, liquidity timing, and pricing mechanics.

What Happens to Employee Stock Options at IPO

  • Vested options: you can exercise vested options and sell shares after lock-up — or exercise and hold if you expect further appreciation.
  • Unvested options: continue vesting on their original schedule after the IPO; the company is now public but vesting is unaffected.
  • ISOs at IPO: the IPO creates a public market, which changes the AMT calculation for ISOs — the spread between strike price and market price can now be large, creating significant AMT exposure if you exercise and hold.
  • Early-exercise and 83(b): employees who early-exercised options before the IPO and filed an 83(b) election generally have long-term capital gains treatment available on the full appreciation, rather than ordinary income at vesting.
  • Post-IPO exercise window: after an IPO, many companies retain the 90-day post-termination exercise window for options — understand your timeline if your employment ends after the IPO but before lock-up expiration.

Example

A software engineer joins a startup three years before its IPO, receiving 50,000 ISOs with a $2 strike price. By the time of the IPO, the company prices shares at $18. The stock opens at $24 on the first trading day. The engineer's options are worth $22/share in intrinsic value (market price minus strike price) — but she cannot sell for 180 days due to the lock-up period. At lock-up expiration, the stock has declined to $16. She exercises her vested 40,000 options and immediately sells in a cashless exercise, netting $14/share ($16 − $2) before taxes. She waits to exercise the remaining 10,000 vested options, hoping the stock recovers — but those options will expire 10 years from grant date if not exercised.