Open interest is the total number of outstanding derivative contracts,such as options or futures that have not been settled for an asset.
To simply put,open interest is a number that tells you how many options contracts are currently outstanding(open) in the market, which means market participants will be watching that market closely.We usually use them as an indicator of trend strength.
As we can see from the chart above, different SPY options trade setups have been initiated but yet to be closed and the majority of them executed on the mid side, usually, they are less indicative for gauging the market participants' sentiment upon the future price action.
Professional participants tend to trade on the put side during the uptrend market atmosphere to protect theirdownside risk and prefer to trade on the mid price for convenience trade purposes since there is less willingness to get the trade done.
So what we are looking into here is the transactions with a tendency as mentioned above that either leaningon the long or short side to determine professional participants' actual sentiment for the future market movement.
Sell put and the long call stood out here in this case,put sellers and call buyers lose money if the stock price falls and therefore the current SPY options chain sentiment from a technical point of view is also a bullish.
2. Notes
For more details, you can check out moomoo's most latest features that will be launched soon so-called "options Xray" icon in the toolbox(upper left corner) under the 'trade' column. By monitoring this market data,traders can create strategies that capitalize on this often over looked information.