The U.S. stock market closes at 4 pm EST. It reopens the following trading day at 9:30 am EST. There is some after-hours and pre-market trading, but the opening and closing create bottlenecks when a lot of orders are piled up, waiting to get filled.
The opening imbalance only orders are meant to provide liquidity at the opening bell for the NASDAQ. They help match other open-only orders set by other traders.
The OIO deals are limit orders, meaning they have a specific price assigned. In other words, they aren't market orders that fill no matter what the price of the stock happens to be. The transactions only complete if their price is reached at the open (they tend to be priced either aggressively high or aggressively low) and are there to fill in when imbalances occur.
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Finance: What is Best Execution?2 Views
Finance allah shmoop What is best execution it's a toss
up between marie antoinette william wallace and berlin ned stark
and well this guy all right well in finance land
however best execution happens when a broker in a transaction
is giving the client the best price and service possible
That might mean choosing the lowest prices on offers if
the clients buying stocks or it might mean doing some
fancy footwork financially to make a trade move smoothly and
quickly that is the broker acting on behalf of her
client is executing the transaction Best A client cletus wants
a million shares of whatever dot com you the broker
can offer a first traunch or ten percent of the
order or one hundred thousand shares at twenty three thirteen
But when you look on the computer matching box grid
there's an offer to sell a million at the higher
price of twenty three eighteen if those million higher price
shares are sold suddenly in a block to someone else
and glam o there's no supply in the market Well
the stock likely pops You'd guess it would print up
twenty maybe thirty cents a share within fifteen seconds of
that trade getting announced well the client wanted a million
shares but you the broker only got him one hundred
thousand shares And yes you got it form a twenty
three thirteen but that was only ten percent of what
he wanted And now the best offer to buy those
shares is twenty three Forty So yes you've got the
first hundred thousand shares cheap but you didn't do what
your client wanted or order So what was the best
execution in this case Well you should have gotten cletus
the million shares a twenty three eighteen That was the
way to go and would've been the best execution of 00:01:45.308 --> [endTime] this trade Way better than this one
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