Different stock market value between sources?

Question

I like to watch my stocks on Yahoo! Finance because it is easier for me to see what is going on. However, when they are doing well according to Yahoo, my Scottrade account does not always reflect it. The market values will be different between the two sources. Why is this?

Answer 1

Yahoo is not a real time source for quotes.  Info is delayed by 15-20 minutes.  Likely your Scottrade account is, and that is why you have a discrepancy.

Answer 2

Broker/dealers receive all their market information, quotes and prices directly from the floor of the exchanges, therefore they are accurate and current,

All other sources have to receive exchange information from vendors or agree to receive delayed information.   This is part of the rules of the exchanges, since their members are the only ones permitted to be provided with current information.