quite specifically, I'm trying to understand why the my request results show both of these RICs, which supposedly refer to the same option, so why are they different?
(notice the second X)
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To my best knowledge, in RICs, case is always meaningful, i.e. I would suppose that the two RICs with case difference are indeed different.
I have run them via RIC Search Tool:
SPXx152318000.U - OPRA S&P 500 Index Option 1800 Put Dec 2023
SPXX152310000.U - OPRA S&P 500 Index Option 100 Put Dec 2023 and OPRA S&P 500 Index Option 1000 Put Dec 2023
Strike price differs, it's a different option, from my observation.
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