But I want to invest now!

Investors may start to get antsy waiting for a company to formally go public on an exchange. 

And companies that are IPOing may not be available for trading for a couple of hours after the market opens. 

So, why is that? 

Tim Anderson, managing director at TJM Investments, explained why investors have to wait to invest in companies that have just gone public. He used Real Money Stock of the Day Uber (UBER) as his example. 

"It takes time to get all of the aftermarket orders put together. Some of them are market orders, some of them are limit orders and then it will take time to get what they would call the right price for the opening. And really what that would be is the price where all of the buyers and sellers that match up. There will be some people that want to add to their position that maybe didn't get as much stock as they put in for on the initial opening," explained Anderson. "There'll be some retail people that were probably completely shut out that may want to buy the stock, but there will also be some people that bought the stock and for a multitude of different reasons, just want to sell part of it on the opening and they want to go back to everybody that was involved in the deal on the customer side with the price indications."

Related. Uber IPO: Sit Back and Enjoy the Volatile Ride

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