What about just trading back and forth intraday? I'm not saying that makes a lot of sense it's just another possibility. If I have 500 contracts and buy 3000 more in the first 3 hours of trading but sell them again before close the OI will stay the same.
How else would there have been volume of 4000 in the March5 calls yesterday and today the open interest barely moved if they weren't being exercised immediately
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