Russell is clamping down on multi-class shares, too: https://research.ftserussell.com/products/downloads/FTSE_Rus...

"Going forward, eligible companies need to have at least 5% of voting rights held by the public. Companies with multiple share classes already in one of the indices will have until September 2022 to change their structures or face removal." ( https://www.dividend.com/news/2017/11/03/companies-multiple-... ). Same link as before.