How does a company go public?

Every listed company you can trade — including your anchor — once had a first day on the exchange. That door between private and public is the IPO, and understanding it snaps the "primary vs secondary market" distinction from Course 1 into focus.

From private to public

A private company's shares belong to founders, employees and early investors — and mostly can't be bought by you. An Initial Public Offering changes that:

1. The company hires investment banks (underwriters) to manage the process.
2. It publishes a prospectus — a legally binding disclosure of its business, finances and risks (often hundreds of pages; the risk section is famously sobering reading).
3. Banks gauge demand from big investors and set an offer price.
4. On listing day, the new shares begin trading on the exchange — and price discovery passes from bankers' estimates to the open market you know.

Primary vs secondary — now it clicks

The IPO sale itself is the primary market: money flows TO the company (or early holders selling their stakes) in exchange for newly public shares. Everything afterward — including every trade you'll ever make — is the secondary market: investors trading with each other, the company not involved. One event separates the two worlds.

The door out

The door swings both ways. A listed company leaves the exchange in one of three ways, and each looks different in your account. Acquired for cash: on the closing date the shares vanish and the agreed price per share arrives as cash, whatever the market printed the day before. Acquired for stock: the shares are replaced by the buyer's shares at the announced ratio, so the count changes and the ticker changes. Delisted: the exchange removes the company for failing its standards or for bankruptcy, and the shares usually keep trading on the OTC market under a new ticker at a fraction of the old price. All three leave a trace in market data: the ticker change is recorded, and the departed company moves onto a list of delisted names, where it waits for you in the data-literacy unit next course.

What IPO headlines actually mean

• "Priced at $21, opened at $30" — demand outran the offer price; the first-day "pop" rewarded those allocated shares at $21 (mostly institutions), not the company, which sold at $21.
• "IPO postponed due to market conditions" — companies prefer calm, receptive markets; volatility closes the IPO window.
• "Lock-up expiry" — insiders typically agree not to sell for ~6 months after listing; when that clock ends, supply can jump. It's a scheduled event, published in advance.

New listings are exciting and historically turbulent — young public companies have short track records and wide outcome ranges. Observation, as always, before participation.

In the data

An IPO calendar is that door in rows. Here are two listings from August 2026:

A row moves through stages: expected, while the banks gauge demand and quote a price range; then priced, once the offer price is set and the shares are sold. The second listing is still at the range stage. The first says priced, and its offer price reads zero. That zero is not a price: an IPO calendar often writes 0 where it means "not known yet". Across 2025 only about a fifth of the listings marked priced carried an offer price at all (counted on 29 September 2026). So the stage label tells you where a deal stands, and the money it raised has to come from the prospectus or the news.

Try it now

1. Look up a company's IPO date — how long has it been public? Apple's is the IPO date row below; for your own anchor company, open it in the Terminal and change the symbol there. Then find the earliest years on the max chart. The early prices look like a flat line near zero, because the chart is adjusted for every split since, and Measure is how you find out the flat line was not flat.

Open AAPL.US in the EODHD Terminal

2. Go back to the IPO calendar above and take the second listing, the one still at the range stage. Multiply the low end of its range by its share count, then the high end. You get two products, a floor and a ceiling on what the company hopes to raise, and the width between them is how much the banks still do not know about demand.
3. Now try the same on the first listing, the priced one: offer price times shares. The answer is zero — a company that sold 17 million shares and raised nothing, printed with total confidence. We counted the whole of August 2026 on 29 September: 134 rows, 24 of them marked priced, and not one with an offer price above zero. You have measured the trap in the section above rather than read about it.
4. Note the exchange too — you now read an IPO line like a professional reads it.