Ah, I stand corrected. I tried to look more into the decision. These seem to be the two relevant quotes: >Companies with multiple share class structures tend

Ah, I stand corrected. I tried to look more into the decision. These seem to be the two relevant quotes: >Companies with multiple share class structures tend to have corporate governance structures that treat different shareholder classes unequally with respect to voting rights and other governance issues >S&P Dow Jones Indices also said that the S&P Composite 1500 indexes, like the S&P 500, follow “more restrictive eligibility rules,” such as positive earnings based on accepted accounting rules whereas its other index groups were “intended to represent the investment universe.” So I suppose they aren't really "the very least picky possible investors". Their mandate seems to include actively curating the S&P 500, despite its tendency to be used by "passive" investors.