Retail don't move the market, but sometimes they get things right. Retail positioning data is available from all CFD providers - IG, CMC, FXCM etc. It's useful to identify extreme sentiment.
Going short via CFDs vs buying cheap puts are different. In the latter case, the insurance protects against downside while allowing you to let winners run. Those going short via CFD deposit the margin with their broker and win/lose money depending on how accurate they are based on their entry point. If they're short during dividend payout, they have to pay the dividend out of pocket while maintaining the short position. They also pay interest. Further, the broker can trade against you by going long if you're short and squeeze you out. If you're trading size on CFDs, the broker will transfer the risk to liquidity provider - i.e. a big insto or bank who has more money and time than retail and can force retail to burn premium. CFDs are instruments that are useful for hedging, but as speculative tool, they're not nearly as profitable as buying shares. Yet, the marketing rubbish says that CFDs allow you to make quick profits with leverage.... Very few manage to do this successfully. Hence, as a tool, CFD positioning is useful to gauge mass sentiment, but it's not necessarily something that's powerful indicator of a big market move. Underlying position data such as those on XJO/SPX, Volume profiles, analyzing auction behavior, knowing seasonal patterns etc are more useful.
I'm still new and learning...
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