> "Right now, there isn’t a level playing field among different parts of the market: wholesalers, dark pools, and lit exchanges. Further, the markets have become increasingly hidden from view. In 2009, off-exchange trading accounted for a quarter of U.S. equity volume. Last year, during the meme stock events, that share swelled to a peak of 47 percent.[2] What's more, 90-plus percent of retail marketable orders are routed to a small, concentrated group of wholesalers that pay for this retail market order flow.[3]"

Source: https://www.sec.gov/news/speech/gensler-remarks-piper-sandler-global-exchange-conference-060822

Wikipedia disagrees with this official SEC statement.

According to https://en.m.wikipedia.org/wiki/Lit_pool

> "The majority of trades, 70%, are transacted over lit pools"