Bloomberg article highlights risks that index rule changes pose to passive investment funds

[https://www.bloomberg.com/news/articles/2026-03-18/spacex-fueled-index-rethink-draws-fire-with-trillions-at-stake](https://www.bloomberg.com/news/articles/2026-03-18/spacex-fueled-index-rethink-draws-fire-with-trillions-at-stake) The article talks about (1) the shortening of the "seasoning" period before listed firms can enter the index (allowing large-caps to break into indexes without price discovery) and (2) the reduction of minimum float thresholds (allowing large-caps to float small amounts of shares to inflat prices). My favourite quote from the article: "Index funds are supposed to be mechanical, rule-following, indifferent to the identity of the stocks they hold, and insensitive to valuation. But when an index provider rewrites rules with specific listings in mind, is the benchmark passively reflecting the market, or actively shaping it?"