Earlier quoted context omitted.
Thanks for the detailed response. I don't get the relevance to the question discussed, though (not your fault).
VLM wrote about it excellently from the buyer's side, but I was thinking about it more from the market side. Depending on the weighting method of the index you're tracking (and other indices that include your stocks), the indices need to rebalance purely in response to "price changes happened and reallocation is needed." This requires buying at minimum (or buying and selling as VLM pointed out). That buying moves the…
I think the relevant mispricing introduced by passive investing is the relative one. The question is not that passive investors are driving the S&P 500 index higher than it should. The thing is that they are failing to distinguish company A, which should ouperform because it's doing well, from company B, which should underperform because it's not doing so well.