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How stock exchanges work
Where a stock order can go, how exchanges and market makers fit in, and what the listing on a 10-K actually tells you, with Apple's 10-K as the listing example.
The short answer
A stock exchange is a registered market where buy and sell orders in listed stocks can meet. When you place an order with a broker, the broker chooses where to send it: to the listing exchange, to another exchange, to a market maker, or to an electronic network that matches orders. A listing on a company's 10-K tells you which exchange officially registers that class of stock, not which market will fill every trade.
Where an order can go
The SEC's investor publication Trade Execution: What Every Investor Should Know walks through the path of an order. For a stock listed on an exchange such as the New York Stock Exchange, a broker may send the order to that exchange, to another exchange, or to a "third market maker": a firm that stands ready to buy or sell a listed stock at publicly quoted prices. For a stock that trades in an over-the-counter market such as Nasdaq, the broker may send the order to a Nasdaq market maker in that stock, or route a limit order to an electronic communications network that matches buy and sell orders at specified prices. The broker may also fill the order from the firm's own inventory, a practice the publication calls internalization.
The same publication says a broker has a duty to seek the best execution reasonably available for its customers' orders, looking at factors such as the opportunity for a better price than the public quote, speed, and the likelihood that the order will be filled. No SEC rule requires a trade to be executed within a set number of seconds, and the quote on a screen is good only for a stated number of shares, so the fill can differ from the price a person just saw.
What a listing on the 10-K means
The cover of a 10-K lists each class of securities registered under Section 12(b) of the Exchange Act, the trading symbol, and the exchange on which that class is registered. That is the official listing. It is not a promise that every trade in the stock will occur on that venue. Apple's fiscal 2026 10-K states that the company's common stock is traded on The Nasdaq Stock Market LLC under the symbol AAPL.
- The listing exchange is the market named on the 10-K cover for that class of stock.
- A broker may still send an order to a different exchange, a market maker, an electronic network, or the firm's own inventory.
- Best execution is a duty the broker owes the customer; it is not a promise of a particular price.
Common questions
What is a stock exchange?
A registered market where orders to buy and sell listed stocks can be executed. The New York Stock Exchange and Nasdaq are the two U.S. exchanges most often named on large-company 10-Ks.
Does a Nasdaq-listed stock only trade on Nasdaq?
No. The 10-K tells you where the class is registered. A broker may send an order to that exchange or to another market center that trades the same stock.
What is a market maker?
A firm that stands ready to buy or sell a stock at publicly quoted prices. The SEC's trade-execution publication describes third market makers for exchange-listed stocks and Nasdaq market makers for Nasdaq stocks.
What does best execution mean?
A broker must seek the most favorable terms reasonably available for customer orders, considering price, speed and the likelihood of a fill, among other factors.
Where does a company report its listing?
On the cover of its 10-K, in the table of securities registered under Section 12(b): the class, the trading symbol and the exchange.
Disclosures
- Editor holdings
- The editor holds no position in any company named on this page. As of Nov 11, 2026.
- Compensation
- Nobody paid for this page. No affiliate links on this page.
- Sources
- Each company's own SEC filings, linked next to each number.
- Last updated
- Nov 10, 2026
General education, the same for every reader. Not a recommendation to buy, sell or hold any security, and it doesn't consider your situation.
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