None of that is correct. 'Series' or 'parallel' are the wrong way to think about things. If you buy 100 shares of AAPL and then you buy a put on SPY, that posit

None of that is correct. 'Series' or 'parallel' are the wrong way to think about things. If you buy 100 shares of AAPL and then you buy a put on SPY, that position is objectively lower risk than the unhedged AAPL position. Your point about counterparties is irrelevant, as I didn't claim that a hedge causes risk to go to zero - merely that it reduces it. It is possible for two risky things to cancel one another (or some components of one another, as in the AAPL/SPY example, the SPY put hedges AAPL's beta).