What is 'Open Interest'
Open interest is the total number of options and/or futures contracts that are not closed or delivered on a particular day.
2. The number of buy market orders before the stock market opens.
BREAKING DOWN 'Open Interest'
1. A common misconception is that open interest is the same thing as volume of options and futures trades. This is not correct, as demonstrated in the following example:
On January 1, A buys an option, which leaves an open interest and also creates trading volume of 1.
On January 2, C and D create trading volume of 5 and there are also five more options left open.
On January 3, A takes an offsetting position, open interest is reduced by 1 and trading volume is 1.
On January 4, E simply replaces C and open interest does not change, trading volume increases by 5.

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What is the difference between open interest and volume?
Learn more about options, what options' volume and open interest are and the difference between volume and open interest ... Read Answer >> 
How do I measure option liquidity?
An option is a financial instrument that gives the holder the right to purchase shares in a company at a certain set price ... Read Answer >> 
What does high open interest tell you about an option?
Learn about the open interest of options contracts and what a high and a low open interest indicate about the liquidity of ... Read Answer >> 
What does a falling open interest on a stock signal?
Learn what falling open interest on a stock signals. Open interest is like volume for options. It is considered a leading ... Read Answer >> 
What are the benefits of using open interest as an indicator?
Find out more about the open interest of option contracts, what the open interest indicates and the benefits of monitoring ... Read Answer >> 
What does a rising open interest on a stock signal?
Learn more about the open interest on stock options, what the open interest of calls and puts indicates, and what a rising ... Read Answer >>