The asking investor can specify her price by putting a limit order through her broker. I just set my bid. I, too, can enter my bid through a limit order online. Once the online brokers receive the requests, they pass them to a middleman, a marketmaker. The marketmaker matches all the orders coming in from investors.
Stock prices change constantly because there are millions of transactions going on at the same time.
Let's say yet another investor wants to sell 100 shares of Dell. I'll lower my bid to get a better price. If enough people lower their bids, and there are more sellers than buyers, the stock will go down. TechTV Inc. All rights reserved. We respect your privacy .